Bio: Vipin Jain is an academic researcher from Arc International. The author has contributed to research in topics: Boride & Boriding. The author has an hindex of 2, co-authored 2 publications receiving 154 citations.
TL;DR: In this article, the optimum pack thickness required to form boride coating of adequate thickness and property in the case of a low carbon steel boronized at 940°C for 2 h.
Abstract: Boronizing, which involves diffusion of boron atoms into steel substrate to form iron borides, is a well-known diffusion coating process and numerous studies have demonstrated the outstanding tribological properties of boronized steel vis-a-vis carburized or nitrided steels However, the high cost of the boronizing process has severely limited its applications One way to bring down the cost of the boronizing process is to reduce the thickness of the boronizing mixture to be packed around the component (called pack thickness) to the minimum required level without compromising on the properties of the boride coating The present study attempts to estimate the optimum pack thickness required to form boride coating of adequate thickness and property in the case of a low carbon steel boronized at 940°C for 2 h Low carbon steel samples have been boronized with varying pack thickness in the range 2-25 mm and the resulting boride coatings have been examined for thickness, microstructure, microhardness profile and abrasion resistance An analysis of the results obtained indicated that a pack thickness of 10 mm is sufficient to obtain boride coatings of adequate thickness and optimum properties
TL;DR: In this paper, a low activity boronizing mixture was used for pack boriding of a medium carbon steel to obtain a single phase Fe2B layer, which is desirable in the boride coating for its superior performance and can be achieved in several ways.
Abstract: Tribological properties such as abrasion and erosion resistance of boride coatings on steels have been proven to be outstanding when compared with conventional hardening techniques, e.g., carburizing and nitriding. Pack boriding is a relatively simple and economical technique among all the methods available for boriding. A single phase Fe2B layer is desirable in the boride coating for its superior performance and this can be achieved in several ways. However, the boride coating is often associated with inherent porosity, especially near the surface and this is undesirable from the standpoint of structural integrity of the coating particularly for applications involving highly loaded parts. Laser-based postprocessing is an effective technique for eliminating these undesirable microstructural features without deteriorating the mechanical properties of the coating. In the present investigation, a low activity boronizing mixture was used for pack boriding of a medium carbon steel to obtain a single phase Fe2B...
TL;DR: In this article, the diffusion coefficient of boron in FeB and Fe 2 B phases is obtained through fitting the experimental results into the model, and the simulation results are found to be in good agreement with experimental results.
TL;DR: In this paper, the mechanical properties of borides formed on AISI H13 hot work tool and AisI 304 stainless steels have been investigated, and the boride layer has a flat and smooth morphology in 304 steel while H13 steel was a ragged morphology.
TL;DR: In this paper, the accuracy of the produced 3D structures in the range of 0.1mm is the highest possible in the group of welding techniques, while the heat input into the workpiece is less compared to TIG or PTA welding, although a metallurgical bonding to the substrate is guaranteed.
Abstract: Surface coating, repair, and rapid design changes of high-value components and tools are demanding challenges of modern manufacturing technology. In this field, advanced laser-based techniques are of outstanding importance for the related applications in mould and tool, aircraft and aerospace, as well as automotive industry. Many laser cladding solutions have been transferred into industrial series production within the last years. The motivations for the raising interest are given by the typical features of the technology: on the base of closed CAD/CAM chains, a quick and comprehensive treatment even of complex shaped and highly stressed components is possible. The heat input into the workpiece is less compared to TIG or PTA welding, although a metallurgical bonding to the substrate is guaranteed. Furthermore, the precise material deposition even at small partial areas is an advantageous characteristic. The coating materials include metal alloys (Co, Ni, Cu basis, Titanium, and steel), hard metals (e.g., WC/Co, TiC, and VC with metallic binders), and oxide ceramics (Al2O3/TiO2). Typical base materials are steel, cast iron, and lightweight metal alloys based on Aluminum, Titanium, and Magnesium. The accuracy of the produced 3D structures in the range of 0.1 mm is the highest possible in the group of welding techniques. On the other hand, the available system technology (lasers, powder feeders and nozzles, CAD/CAM systems) permits a very easy and successful integration of the laser technology into manufacturing systems. Examples of application are the surface protection of lightweight automotive motor components, repair and quick modifications of metal forming tools as well as the complete restoration of damaged blades and disks of aero engines and gas turbines.
TL;DR: In this article, the extent of penetration of FeB and Fe2B sublayers was measured as a function of boronizing time and temperature in the range of 1123-1273 K. The results showed that K increase with boriding temperature.
Abstract: In present study, kinetic studies on borided AISI 5140, AISI 4340 and AISI D2 steels are reported. Steels were borided in a salt bath consisting of borax, boric acid and ferro-silicon between 1073 and 1273 K for 2, 4, 6 and 8 h. The morphology and types of borides formed on the surface of steel substrates were confirmed by optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Boride layer thickness formed on the borided steels ranged from 21 to 238 μm depending on process temperature, treatment time and alloying elements of the substrates. The hardness of borides formed on the samples changes between 1077 and 2140 HV0.1 according to treatment time and temperature. Layer growth kinetics were analyzed by measuring the extent of penetration of FeB and Fe2B sublayers as a function of boronizing time and temperature in the range of 1123–1273 K. The depth of the tips of the most deeply penetrated FeB and Fe2B needles are taken as measures for diffusion in the growth directions. The kinetics of the reaction, K=Ko exp (−Q/RT), have also been determined by varying the boriding temperature and time. The results showed that K increase with boriding temperature. Activation energies (Q) of borided AISI 5140, AISI 4340 and AISI D2 steels at present study were determined as 223, 234 and 170 kJ/mol, respectively. Moreover, an attempt was made to investigate the possibility of predicting the contour diagrams of boride layers variation and to establish some empirical relationships between process parameters and boride layer thicknesses.
TL;DR: In this article, the fracture toughness of boride formed on surfaces of 99.97% pure iron, depending on the process time, ranged from 3.59 to 3.83 MPa m1/2.