Filler metal

About: Filler metal is a research topic. Over the lifetime, 11152 publications have been published within this topic receiving 86590 citations.

Aluminum alloy brazing fin material for heat exchanger

Abstract: PROBLEM TO BE SOLVED: To provide an aluminum alloy brazing fin material for an automobile heat exchanger using an aluminum tubular body in which a Zn covering layer is formed and subjected to no chromate treatment, whose formability is excellent, and in which the generation of pitting corrosion in the aluminum tubular body is suppressed in a severe corrosive environment, further, the corrosion resistance of a brazed part is excellent, and the departure of a fin from the aluminum tubular body can be prevented. SOLUTION: The aluminum alloy brazing fin material is obtained by cladding an Al-Si-based alloy brazing filler metal on both the sides of a core material. The core material is composed of an aluminum alloy comprising 0.8 to 2.5% Mn, 0.1 to 1.0% Si, 0.06 to 0.3% Fe and 0.8 to 4.0% Zn, and the balance Al with impurities. The brazing filler metal is composed of an aluminum alloy comprising 6 to 13% Si and 0.06 to 0.4% Cu, and the balance Al with impurities. The brazing filler metal is clad on both the sides of the core material, respectively, at a thickness of 3 to 20% to the whole thickness. COPYRIGHT: (C)2005,JPO&NCIPI

Dual-beam laser welding of ultra-thin AA 5052-H19 aluminum

Abstract: Welding of 0.05 mm (0.002 inch) thin AA 5052-H19 aluminum samples in lap-joint configuration was conducted autogenously (no filler metal) using dual lasers that included Nd:YAG and diode with a zero inter-beam spacing. The 70-ns pulsed Nd:YAG (1064 nm) laser acted as the welding tool while the continuous wave diode (810 nm) laser with interaction times of 40–120 ms served to improve the light absorption characteristics of aluminum through preheating and oxidation effects. The microstructure, composition, flaws, and hardness of the joint were evaluated by scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction, and micro-indentation hardness test. The dual-beam welding technique was also compared with single-beam (Nd:YAG) welding. Results of parametric effects are displayed in the form of processing maps. Deeper penetration, better weld quality (less humping and cutting), and increased hardness were observed in dual-beam welds when compared with single-beam welds. The most astounding result was a nearly 200% increase in hardness over the base metal in dual-beam welding. This can be explained by the oxygen pickup in a dual-beam weld due to longer heating and amorphous microstructure of aluminum oxide as revealed by energy dispersive X-ray spectrum and X-ray diffraction respectively.

Development of welding technology for improving the metallurgical and mechanical properties of 21st century nickel based superalloy 686

Abstract: Alloy 686 is a highly corrosion resistant 21st-Century Nickel based superalloy derived from Ni-Cr-Mo ternary system. The alloying elements chromium (Cr) and molybdenum (Mo) are added to improve the resistance to corrosion in the broad range of service environment. The presence of a higher percentage of alloying elements Cr and Mo lead to microsegregation and end up with hot cracking in the fusion zone of Nickel-based superalloys. However, there is scanty of information regarding the welding of alloy 686 with respect to the microsegregation of alloying elements. The present study investigates the possibility of bringing down the microsegregation to cut down the formation of secondary phases in the fusion zone. The weld joints were fabricated by Gas Tungsten Arc Welding (GTAW) and Pulsed current gas tungsten arc welding (PCGTAW) with ERNiCrMo-10 filler and without filler wire (autogenous) mode. The microstructural properties of the weld joints were studied with optical and Scanning Electron Microscope (SEM). The joints fabricated by pulsed current (PC) technique shows refined microstructure, narrower weld bead and practically no heat affected zone (HAZ). Scanning Electron Microscope demonstrates the presence of secondary phases in the interdendritic regions of GTAW case. Energy Dispersive X-ray Spectroscopy (EDS) analysis was carried out to evaluate the microsegregation of alloying element. The results show that the segregation of Mo noticed in the interdendritic zone of GTAW both autogenous and filler wire. Tensile and Impact tests were done to evaluate the strength, ductility, and toughness of the weld joints. The results show that the PCGTA helps to obtain improved strength, ductility and toughness of the weld joints compared to their respective GTAW. Bend test did not lead to cracking irrespective of the type of welding adopted in the present study.

Apparatus for connecting metallic parts by means of arc fusion welding

Abstract: An apparatus for connecting metallic parts, and metallic parts so produced, by means of arc fusion welding by producing a low volume welding seam (narrow gap welding), wherein the workpiece parts to be joined and forming a narrow gap are initially welded at their butt joint by means of, for instance, electron-beam welding, plasma-arc welding, laser-beam welding or argon arc-welding to produce a base seam with or without filler material, and thereafter the workpiece flanks forming the narrow gap are united by alternately depositing weld beads at first one and the other workpiece flank by submerged-arc welding