Showing papers on "Spray forming published in 2017"

Characterization of plasma-sprayed carbon nanotube (CNT)-reinforced alumina coatings on ASME-SA213-T11 boiler tube steel

Abstract: In this research work, carbon nanotube (CNT)-reinforced Al2O3 coatings were prepared and successfully deposited on ASME-SA213-T11 boiler tube steel. Coatings were deposited by the plasma spray process. Ni-Cr was also used as a bond coat before applying CNTs-Al2O3 coatings. The coatings were subjected to metallography, XRD, SEM/EDAX, and X-ray mapping analysis. The porosity of CNT-Al2O3 mixed coatings was decreasing with increase in CNT content. The CNTs were found to be uniformly distributed within the Al2O3 matrix. The CNTs were chemically stable during the spray forming. It did not react to form oxides or aluminum carbides even at the very high processing temperature.

Wear and corrosion properties of HVOF coatings from Superduplex alloy modified with addition of boron

Abstract: Fe-based protective coatings are promising alternatives to replace large or expensive mechanical structures in aggressive environments, such as, in petrochemical industries. In this work, we have evaluated the corrosion and abrasive wear resistance of coatings produced by the HVOF thermal spray process using the commercial SAF2507 Superduplex alloy modified by the addition of 3.0 wt% boron. Three coatings were obtained from different metal powders produced by different routes (spray forming and high energy ball milling). The coatings had a partially amorphous structure containing a dispersion of nanocrystalline borides, such as Fe 3 B and (Fe,Cr) 2 B. The coatings showed significant improvement in abrasive wear resistance and preserved the high corrosion resistance of the commercial SAF2507 Superduplex alloy.

Electrochemical Corrosion Behavior of Spray-Formed Boron-Modified Supermartensitic Stainless Steel

Abstract: Spray-formed boron-modified supermartensitic stainless steel (SMSS) grades are alloys developed to withstand severe wear conditions. The addition of boron to the conventional chemical composition of SMSS, combined with the solidification features promoted by the spray forming process, leads to a microstructure composed of low carbon martensitic matrix reinforced by an eutectic network of M2B-type borides, which considerably increases the wear resistance of the stainless steel. Although the presence of borides in the microstructure has a very beneficial effect on the wear properties of the alloy, their effect on the corrosion resistance of the stainless steel was not comprehensively evaluated. The present work presents a study of the effect of boron addition on the corrosion resistance of the spray-formed boron-modified SMSS grades by means of electrochemical techniques. The borides fraction seems to have some influence on the repassivation kinetics of the spray-formed boron-modified SMSS. It was shown that the Cr content of the martensitic matrix is the microstructural feature deciding the corrosion resistance of this sort of alloys. Therefore, if the Cr content in the alloy is increased to around 14 wt pct to compensate for the boron consumed by the borides formation, the corrosion resistance of the alloy is kept at the same level of the alloy without boron addition.

Processing of High-Entropy AlCoCr 0.75 Cu 0.5 FeNi Alloy by Spray Forming

Abstract: Compositionally complex AlCoCrCuFeNi alloy system is one of the extensively studied high-entropy alloys (HEA). Most of these studies have been carried out on as-cast materials that witness slow cooling rate during solidification. In the present investigation, HEA based on AlCoCrCuFeNi system was processed employing spray forming so as to realize its inherent rapid solidification effect and unique microstructural evolution mechanism. The spray formed as well as the as-cast alloys were compared in terms of their microstructural features, phase constitution and hardness. These microstructural features were also compared with that of the overspray powders (< 250 µm) obtained as a by-product of spray forming. Both the as-cast and spray formed alloys showed a mixture of mainly two phases, i.e., face-centered and body-centered cubic (BCC) phases, in contrast to a single BCC phase in overspray powders. However, the spray formed alloy revealed unidentified phases, as against the as-cast material, which disappeared after heat treatment at 1473 K for 3 h. The grain size of the as-cast alloy was around 600-1000 μm compared to a highly refined grain size of 25-30 μm in the as-spray formed alloy. It was found that the hardness of the regions dominated by the constituent phases as well as the bulk of the spray formed material was higher than that of the as-cast alloy. The results validate the efficacy of the process in achieving drastic refinement in grain size, in a single step of large-scale spray forming. The characteristic microstructural features and the phase constitutions have been discussed in light of the prevailing mechanisms of structural evolution and possible solidification phenomena during spray atomization and deposition. This study gives a new direction in processing of these alloys and understanding their solidification behavior under the conditions of layer-by-layer deposition of semi-solid/liquid droplets.

Thermodynamic Calculations for the Investigation of Phase Formation in Boron-Modified Ferritic Stainless Steel

Abstract: Thermodynamic calculations in equilibrium condition were used to investigate the phase formation sequence and microstructure formation in a boron-modified ferritic stainless steel. The results were also compared with spray forming experimental heats. The thermodynamic calculations indicated that there is an eutectic point at around 1.1 wt.% B and therefore two different compositions (hypo and hypereutectic) were experimentally investigated. For the hypoeutectic composition, the primary phase to form from the melt was δ-ferrite with the boride phase M2B originating eutectically. Conversely, for the hypereutectic composition, the boride M2B was formed as the primary phase. The prediction of phase formation and stable phases at room temperature was accurate. The calculated melting temperatures showed considerable deviation from values measured by Differential Scanning Calorimetry. The final spray formed microstructure and the phase fractions were to some extent in accordance with the thermodynamic calculations.

3-d printing using spray forming

Abstract: Techniques for 3-D printing parts using spray forming are disclosed. A 3-D printer receives instructions for printing a structure, where the instructions based on a data model of the structure. The 3-D printer receives a suitable material such as a metal, plastic, or composite, and prints the structure based on the instructions using spray forming. In one embodiment, the 3-D printer employs spray forming to finish an angled surface of a 3-D printed part having a stair-stepped effect.

High-strength and high-toughness multi-element Al-Cu alloy and preparation method and application thereof

Abstract: The invention discloses a preparation method of a high-strength and high-toughness multi-element Al-Cu alloy. The preparation method comprises the following steps: raw materials is heated into a molten state, spray forming process is carried out through spray forming equipment, so that the multi-element Al-Cu alloy is formed, and the multi-element Al-Cu alloy is composed of Al, Cu, Mn, Ni, V, Sc, impurity Si and Fe. According to the preparation method, the high-strength and high-toughness multi-element Al-Cu alloy material for a lightweight cartridge case is prepared through the proportion of the raw material components, based on the micro-alloying component design of a Al-Cu alloy system and by combining 3d spraying forming-rapid solidification technology; the high-strength high-toughness multi-element Al-Cu alloy material has the advantages that crystal grains are fine, the structure is uniform, and the high-strength and high-toughness performance is achieved; according to the structure and the performance of the multi-element Al-Cu alloy, a reasonable cartridge case preparation technology is selected so that the use requirements of various lightweight cartridge cases can be met, and the Al-Cu alloy material can also be applied to a shell and a launching component of a short-range, medium-range and even a remote missile; and the Al-Cu alloy material has huge economic benefits.

Spray Forming of Novel Materials

Abstract: Spray forming (SF) can be classified as a three-stage manufacturing process where liquid is disintegrated into a spray of small droplets, droplets solidify in the spray under a relatively rapid solidification condition during their flight and finally ends as the spray deposit builds up on a substrate, with the remaining liquid/semi-solid droplets solidifying at considerably slower rates. Due to a high cooling rate experienced during the atomization and the special conditions of deposit build up, with incoming droplets dynamically refining the solidifying material, as-sprayed deposits typically display a fine-scale microstructure, which may also exhibit some extended solid solubility and metastable phases. In the last few decades, a number of new materials’ classes and process routes have been developed. The world inclination towards the development of newer materials to cater to the presently stringent requirements has led to these innovations. Among them, very promising materials are the amorphous alloys and metallic glasses that show high strength as well as stiffness far above the conventional material classes of similar compositions. Despite such incremental developments, a paradigm shift has been observed in the design of new alloys with low cost alloying elements such as iron, aluminium and magnesium, instead of the costly Pd-, Zr- and La-alloy systems, and in the development of viable processing routes. However, the lower GFA of many of the alloys poses challenge on the process selection and modification. A few research works have demonstrated the development of bulk amorphous, nanocrystalline or a combination of amorphous-nanocrystalline-crystalline materials by spray forming. This chapter describes the results reported so far on spray forming of aluminum- and iron-based alloys, whose compositions are derived from rapid solidification studies aimed at obtaining amorphous structures. Due to the unique effect of the combinations of various process parameters, the processed aluminium-based glass-forming alloys show the formation of amorphous phase throughout the deposit of the Al-based alloy at high Gas to Metal ratio. This is generally not observed in the Fe-based alloys. However, some iron-based compositions displaying the highest glass-forming ability showed a high volume fraction of amorphous phase up to 4 mm thickness of the deposit. A similar value is obtained for this class of material when processed by copper mold casting. The present review, therefore, is an attempt to look into the alloy systems, their glass formability and the efficacy of spray forming in particular, to produce bulk metallic amorphous materials. The chapter also attempts to bring out the prevailing mechanisms during the development of amorphous phase in the bulk deposits, and in light of the process characteristics points out directions for future developments.

The study of preparation process of spray formed 7075/Al–Si bimetallic gradient composite plate

Abstract: To determine the spray forming process parameters of 7075/Al–Si bimetallic gradient composite plate with two gas atomizers, a calculation model of the plate has been established by using the finite element software ANSYS. The effects of different motion trajectory, advance speed, swing cycle and spray center distance on shape, and silicon distribution of deposited plate have been simulated by the APDL programming language. The results show that a smooth and uniform surface is obtained when motion trajectory is in a regular jaggies mode. The deposited plate varies from platform to stepped shape with a center distance increasing from 20 mm to 50 mm; meanwhile, the width of the transition zone decreases gradually. As the period increases to 8 s, the silicon distribution of each layer presents a jagged fluctuation. Both the thickness of the deposited plate and the width of the transition zone decrease as the advance speed increases, except the silicon distribution. Finally, the modeling and simulation of the co-spray formed 7075/Al–Si bimetallic gradient composite plate are validated by experimental investigations and the simulation results are in good agreement with the actual results.

Spray forming method for aluminum-lithium alloy

Abstract: The invention discloses a spray forming method for an aluminum-lithium alloy. The spray forming method comprises the following steps that (1) materials are weighed according to mass percentages of chemical components of the alloy; (2) the components of the aluminum-lithium alloy are melted in a smelting furnace, and a covering agent is added for protection, wherein the melting temperature is 700-800 DEG C; (3) alloy melt is refined at the refining temperature of 700-750 DEG C; (4) the refined alloy melt is subjected to standing for 10-30 min, and then filtering is conducted; and (5) the filtered alloy melt is injected into a bottom pouring ladle, and the alloy melt is sprayed from refractory spray nozzles to a receiving plate to be formed. A spray forming device is adopted, and an aluminum-lithium alloy round ingot is accurately formed by adjusting the spraying angle, the atomization air pressure, the melt superheat temperature, and the lowering speed and the rotating speed of the receiving plate, and the spray forming method has the advantages that the compactness of a finished product is high, the chemical components are uniform without macrosegregation, the forming speed is high, the process stability is good, and the rate of finished products is high.

Simulation of jet-flow solid fraction during spray forming

Abstract: A numerical model was developed to simulate the jet-flow solid fraction of W18Cr4V high-speed steel during spray forming The whole model comprises two submodels: one is an individual droplet model, which describes the motion and thermal behaviors of individual droplets on the basis of Newton’s laws of motion and the convection heat transfer mechanism; the other is a droplet distribution model, which is used to calculate the droplet size distribution After being verified, the model was used to analyze the effects of parameters, including the initial gas velocity, deposition distance, superheat degree, and the ratio of gas-to-metal mass flow rates, on the jet-flow solid fraction Finally, an equation to predict the jet-flow solid fraction directly and conveniently according to the parameters was presented The values predicted by the equation show good agreement with those calculated by the numerical model

Method for forging aluminum alloy brake disc brake drum through spray forming

Abstract: The invention relates to a method for forging an aluminum alloy brake disc brake drum through spray forming. The method includes the steps of 1, smelting; 2, spray forming; 3, feeding; 4, forging; 5, heat treatment; and 6, machining. Aluminum alloy with specific components is smelted firstly, a blank is prepared in a spray forming manner, the blank is machined to be in a proper size, a brake disc brake drum forged piece is subjected to forging forming through an oil press and a mold, and finally the brake disc brake drum part is obtained after heat treatment and machining are completed. The method has the beneficial effects that compared with a cast iron brake disc brake drum, the weight of the aluminum alloy brake disc brake drum prepared through the method is reduced by 40-70%, the heat conductivity coefficient is increased by 2-3 times, the mechanical strength is higher, the abrasion resistance is better, accordance with the car light-weight development tendency is achieved, the problem that in a high-speed brake state, the temperature of a system is raised, so that heat fading is caused, and the brake effect is affected can be effectively solved, driving safety is improved, and the service life can be prolonged by 2-3 times than that of the cast brake disc brake drum.

Method for preparing multi-phase reinforced ferrite alloy

Abstract: The invention relates to a method for preparing multi-phase reinforced ferrite alloy and belongs to the technical field of metal dispersion strengthening. A technological process is that firstly, an alloy ingot is purified by adopting a vacuum melting+electroslag remelting double process; spray forming is performed on the purified alloy ingot, mixed gas of inert high pressure gas and oxygen is taken as an atomizing medium, the content of introduced oxygen is controlled through adjusting oxygen partial pressure in the atomizing medium, and an oxygen element is provided for the formation of oxides in the alloy; an alloy blank is thermally extruded, oxidization films on the surfaces of powder particles are crushed in the thermal extrusion process and are distributed again, and the oxygen element is preferentially combined with rare earth elements Y and Ti to form a Y-O or Y-Ti-O oxide dispersion phase. The obtained ferrite alloy is jointly strengthened by an L21 type Ni2AlMn inter-metallic compound, a NiAl inter-metallic compound, a Cu-rich precipitate and the oxide dispersion phase. The method provided by the invention solves the problems of low efficiency and high content of metal and nonmetallic inclusions when a traditional mechanical alloying process is used for preparing a dispersion-strengthened material, so that the comprehensive mechanical properties of the material are improved.

Spray Transport Fundamentals

Abstract: This chapter will present insights into the spray evolution and spray transport process during melt atomization and sprays based on multiphase flow analysis with momentum and energy transfer. Spray processes typically involve the liquid atomization stage and the multiphase phase flow within the spray. In the present example the spray consists of a two-phase flow with melt droplets and gas (metal melt atomization for powder production or spray forming) or even a three-phase flow of solid particles, melt droplets and gas (spray processing of metal-matrix-composites). The evolution of the spray depends on a series of physical phenomena involved initiated by bulk liquid disintegration (i.e. primary atomization), breakup of primary fragments like ligaments and droplets (i.e. secondary atomization), momentum and heat exchange between gas and melt, droplet solidification, droplet-droplet or particle-droplet collisions. The gas flow dynamics, especially in a twin-fluid atomization process, is an important topic here. The physics of atomization of liquid metal into dispersed phases and subsequent spray of those dispersed phases is mainly governed by very high and rapid momentum and heat transfer between the high speed atomization gas phase and the molten metal stream. A detailed introduction is given to the fundamentals of liquid atomization, in which the up-to-date understandings in liquid jet/sheet disintegration mechanism and droplet breakup mechanism, as well as the recent progress in melt atomization and spray process modelling, are presented. The research progress on the kinetic dynamics and thermal dynamics of dispersed phases in spray process, as well as the conclusions from the investigations of droplet-droplet or particle-droplet collision process will be given. At last, a multiscale description of particle-droplet interactions in spray processing of metal-matrix-composite (MMC) particles is described, and thereby the optimized operation condition and spray configuration for the maximum production efficiency of MMC particles in spray processes can be derived.

Aluminium alloy for automobile hub and spray forming process of aluminium alloy

Abstract: The invention provides aluminium alloy for an automobile hub and a spray forming process of the aluminium alloy. The aluminium alloy for the automobile hub comprises the following elements by weight percent: less than 0.15% of silicon, less than 0.15% of iron, 2-8% of zinc, 0.01-6% of copper, 0.01-3% of magnesium, 0.01-2% of zirconium, 0.01-2% of chromium, 0.01-2% of manganese and the balance of aluminium. On the basis of conventional production processes, equipment and techniques of the automobile hub, a high-strength and high-toughness aluminium alloy hub material which is formed by spraying is developed, and the aluminium alloy for the automobile hub has the advantages of high strength, good plasticity, easiness in forging processing and the like, and has a very high practical value and significance on development of the automobile industry.

Rapid Solidification and Laser Cladding of Gas Atomized Ni-Nb-Sn Bulk Metallic Glass

Abstract: Glassy overspray powders of Ni59Nb35Sn6 (at%) bulk metallic glass (BMG) obtained by spray forming were used in order to produce coatings on AISI 1020 mild steel substrate by laser cladding of the pre-placed powders. Different laser parameters, resulting in a variation of the power density, PD (J/mm2), were tested with a Yb fiber laser (up to 500 W). Gas atomized powders, suction cast sample trough copper mold casting and the laser clad tracks were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and coatings were subjected to measurements of Vickers microhardness. Atomized powder obtained showed no crystalline phases formation up to 425 μm, indicating good glass forming ability (GFA) of Ni59Nb35Sn6 (at%) alloy. Microstructure characterization confirmed maximum glassy dimension of tc =1mm for the Ni59Nb35Sn6 (at%). Laser cladding track showed nanocrystalline phases embedded in a glassy matrix with Vickers microhardness ranging from 336 to 1184 HV.

Spray Forming of Steels

Abstract: Spray forming of a wide range of steels and iron based alloys have been investigated since the 1970s. These range from low-alloy carbon steels to high-carbon, high-alloy tool steels. The preform types include round billets, flat deposits, tubular preforms, clad structures, gradient deposits, and molds/dies. While the size of the deposits produced in pilot-scale plants is typically less than 100 kg, the industrial plants are in some cases capable of producing preforms with weight up to several tons. Microstructure and properties of the spray formed steels are usually far superior to those of cast material, typically resembling those of the equivalent powder metallurgy steels. The main advantage of spray forming over powder metallurgy route is the possibility to eliminate powder handling steps. This not only minimizes the risk of contamination but also results in cost savings.

Multi-mode electro-hydro dynamics spray forming device and control method thereof

Abstract: The invention discloses a multi-mode electro-hydro dynamics spray forming device and a control method of the multi-mode electro-hydro dynamics spray forming device. The multi-mode electro-hydro dynamics spray forming device comprises a machine frame, a bearing platform, a liquid spraying module, a platform conversion mechanism and a pattern forming platform. A gap groove is formed in the middle of the bearing platform. The liquid spraying module is arranged on the bearing platform through an X-axis sliding mechanism and the Z-axis sliding mechanism and provided with a liquid spraying mechanism used for spraying solution. The liquid spraying mechanism is used for spraying the solution to a substrate to conduct pattern formation. The platform conversion mechanism is arranged on the bearing platform through a Y-axis sliding mechanism. The platform conversion mechanism comprises two supporting pieces which are in bilateral symmetry and arranged on a Y-axis sliding mechanism in a sliding manner. A rotating shaft is arranged between the supporting pieces. A plurality of pattern forming platforms are axially distributed along the rotating shaft. The pattern forming platform can change the position along with rotation of the rotating shaft. Through the arranged rotatable platform conversion mechanism, the pattern forming platforms are switched through the control method of the multi-mode electro-hydro dynamics spray forming device, so that multi-mode spray formation is achieved, and the demand for formation of different patterns is met.

Preparation method for magnesium alloy

Abstract: The invention relates to the spray deposition preparation process, and discloses a preparation method of high-toughness magnesium alloy. According to the preparation method, a spray forming technology in the protective atmosphere is adopted, so that the problems of volatilization, oxidation, safety and the like of the magnesium alloy are solved, and the mechanical property and the plasticity and toughness of the magnesium alloy are synchronously improved. The method comprises the following steps: firstly, putting an alloy ingot into a smelting furnace, extracting the furnace to a vacuum state, carrying out argon gas slugging for 2-3 times, filling the furnace with argon gas when the vacuum degree is 10-70 Pa until the pressure is slightly lower than the atmospheric pressure of the exterior, melting the ingot, electromagnetically stirring and evenly mixing the melted ingot, then pouring the melted ingot into a tundish when the melt temperature is 700-770 DEG C, making the melted ingot flow out through a flow guide nozzle, atomizing the melted ingot, and finally depositing atomized liquid drops on a receiving pole plate to form columnar magnesium alloy deposition blanks, wherein the annular hole type non-limiting type atomizing nozzle is adopted, high-pressure atomization N2 gas is adopted, and the atomization pressure is 0.5-0.6 MPa. The strength and the toughness of the prepared magnesium alloy are both high and are synchronously improved.

In-Situ, Real Time Diagnostics in the Spray Forming Process

Abstract: The structure and material properties of spray formed products depend directly on the thermal state of the semi-solid droplets before their impact, of the substrate and of the already deposited layer. Monitoring specific droplet properties as i.e. droplet temperature, velocity and size as well as mass and enthalpy fluxes provide a unique tool for optimizing the material properties as well as controlling spraying conditions during deposition (as sketched in Fig. 6.1).

Processing Aspects in Spray Forming

Abstract: Several atomization techniques have been used to spray form a bulk material. Detailed information about those techniques is described in Chapter 2. This chapter focuses on differences in process conditions in spray forming using single fluid and gas atomization as well. Specially, the conditions (e.g. mass flux and enthalpy distribution) in the spray cone of a free fall atomizer are reported in detail. Furthermore, the deposition process is described including topics like overspray, yield, sticking efficiency and temperature history of the deposit. These are important issues with relevance to processes similar to spray forming, such as current thrusts in Additive Manufaturing (AM).

Spray Forming of Copper Alloys

Abstract: Spray forming as a process innovation in the copper industry has opened the door to several cutting-edge technologies for copper alloys. Indeed, spray-formed copper alloys have become “mature” materials within the last two decades and have seen industrial applications in several major key production technologies of the twenty first century. In several fields they have become competitors to classical engineering materials such as steel due to their homogeneous and tailored microstructure allowing production of complex alloy systems with a good combination of strength, ductility, workability and physical properties.

Spray Forming of Aluminium Alloys

Abstract: As mentioned in Chap. 1, Prof. Singer claimed in 1990 four mean targets to make spray forming a success story, which are valid for aluminium alloys, too [90]. These four targets are: Spray forming must first concentrate on premium products. Spray forming may in some cases defeat the conventional product on cost because of near-to-net shape manufacture. Make products that have better properties than competitive ones. Make products that cannot be made by any alternative means. This target will be summarized under the headline “Impossible alloys”.

Microstructural Evolution in Spray Forming

Abstract: Spray forming is a casting process in which the molten metal is directly converted to a solid bulk with unique characteristics. When processed under optimum conditions, spray formed materials typically present microstructures composed of refined polygonal (non-dendritic) grains, uniformly distributed with low levels of micro- and macro-segregation. This set of characteristics is achieved regardless of the alloy system, making spray forming an attractive process to produce alloys where processing by conventional casting techniques is complicated. This chapter is dedicated to presenting the mechanisms that take place when the atomized droplets arrive at the deposit surface, and how the spray-formed microstructures evolve during deposition. It will be seen that spray forming is a self grain-refining casting process and cannot be considered a rapid solidification technique. Section 7.6 will address the main differences between the microstructural evolution in spray forming and other spray deposition or “thermal spray” processes. These processes include plasma spraying, high velocity oxy-fuel, wire arc spraying, detonation gun spraying, etc. In this way, it will show why spray forming is such a unique process. This chapter is also dedicated to presenting how the porosity—an intrinsic feature of spray-formed microstructures—is generated and how the processing parameters affect its type, size and distribution. Furthermore, the generation of other defects related to the solidification and/or to the cooling of the spray formed product after deposition—such as residual stresses and hot cracks—and their influence on the product quality and material properties will be presented. Finally, this chapter will also discuss the effect of the atomization gas (Ar, N2 or He) on the final product quality in terms of porosity and chemical composition of steels, superalloys, and copper alloys.

Classification and Evolution of Porous Defects in Spray-Formed Al–Zn–Mg–Cu Alloy

Abstract: The porous defects classification in spray-formed Al–Zn–Mg–Cu alloy was investigated in this paper during spray forming, hot isostatic pressing (HIP) and homogenization. Metallographic microscopy and scanning electron microscopy (SEM) were used to study the microstructure and porous defects. The results showed that, there were four kinds of porous defects in spray-formed alloy, which were distinguish by the reasons of formation and shape. The first kind, the second kind and the third kind porous defects contain gas, while the forth kind porous defect did not contain gas. The forth kind porous defects can be eliminated by HIP, but the other three only can be compressed to be smaller. After homogenization, the porous defects with gas grew up and was observed easily again, unless some porous defects connected with ingot surface through the other porous defects which could exhaust gas during HIP. The second phase in the ingot restored back mostly after the homogenization treatment of 440 °C/12 h + 474 °C/48 h.

System for reducing temperature of spray forming and method for reducing temperature of ingot blank by adopting system

Abstract: The invention discloses a system for reducing the temperature of spray forming and a method for reducing the temperature of an ingot blank by adopting the system. The system comprises a spray forming device and a cooling system, wherein the cooling system comprises a heat absorbing structure, a cooling device, a circulating power pump, a heat conducting medium and a heat conducting medium conveying pipeline; the heat conducting medium conveying pipeline is connected with the eat absorbing structure, the cooling device and the circulating power pump sequentially to form a heat conducting loop; the heat absorbing structure is positioned in an atomizing chamber of the spray forming device and used for cooling the ingot blank or a tray; the cooling device is positioned outside the atomizing chamber of the spray forming device, and used for cooling the heat conducting medium of which the temperature is increased due to absorption of the heat of atomizing chamber; and under the action of the circulating power pump, the heat conducting medium flows in the heat conducting loop in a circulating manner, thereby achieving heat absorption in the atomizing chamber and heat dissipation in the cooling device. The system disclosed by the invention has the following beneficial effect: the ingot blank or the tray can be directly cooled by adopting the heat conducting medium, and then the ingot blank meeting the performance requirements can be obtained.