Spray forming

About: Spray forming is a research topic. Over the lifetime, 1153 publications have been published within this topic receiving 12869 citations. The topic is also known as: spray casting & spray deposition.

Method for reducing thermally induced porosity in a polycrystalline nickel-base superalloy article

Abstract: A method is provided for reducing the tendency for thermally induced porosity within a γ' precipitation strengthened nickel-base superalloy which has been processed to obtain a uniform and coarse grain microstructure. This method is particularly useful for forming components such as gas turbine compressor and turbine disk assemblies in which optimal mechanical properties, such as low cycle fatigue and creep resistance, are necessary for operating at elevated temperatures within a gas turbine engine. The method generally entails alloying a γ' precipitation strengthened nickel-base superalloy to have a boron content of not more than about 0.02 weight percent, and then forming a billet by melting an ingot of the superalloy in an argon gas atmosphere and atomizing the molten superalloy using argon gas. The above atomizing technique encompasses both powder metallurgy and spray forming processes.

Processing of glass former alloys by spray forming. Herstellung von Legierungen für Glasformen durch Sprühkompaktieren

Abstract: Spray forming (SF) can be classified as a two-stage manufacturing process in which solidification begins during particle flight, a relatively rapid solidification step that ends as the deposit builds up, with the remaining liquid droplets solidifying at considerably slower rates. Due to the high cooling rate of the atomization step and the special conditions of deposit buildup, with incoming materials 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. Our group has studied several alloys in order to investigate the potential formation of novel microstructures by this process. This paper describes some of the results obtained by spray forming of aluminum- and iron-based alloys, whose compositions derive from rapid solidification studies aimed at obtaining amorphous structures. Al85Y8Ni5Co2, Fe83Zr3.5Nb3.5B9Cu1, [(Fe0.6Co0.4)0.75B0.2Si0.05]96Nb4, and Fe63Nb10Al4Si3B20 glass-forming alloys were processed. Formation of amorphous phase was observed throughout the deposit of the Al-based alloy processed at a high G/M ratio, which was not observed in the Fe-based alloys. In addition, the [(Fe0.6Co0.4)0.75B0.2Si0.05]96Nb4 alloy, which displayed the highest glass-forming ability among the Fe-based alloys, showed a high volume percent of amorphous phase formation up to 4mm thickness of the deposit, a similar value obtained for this alloy when processed by copper mold casting.

Optimizing material distribution for tool trajectory generation in surface manufacturing

Abstract: Surface manufacturing is widely used in industry. Automatic CAD-guided tool planning has many applications in surface manufacturing, such as spray painting, spray forming and indirect rapid tooling. Generating tool trajectories for freeform surfaces to satisfy the given requirements is still highly challenging due to the complex geometry of free-form surfaces and the spray gun model. A CAD-guided tool trajectory generation system for free-form surfaces has been developed in our previous work. A material distribution model is also presented. Because of the irregular shape of automotive parts, the spray width may not be a constant. Also the path integration for a part with multiple patches may need the spray width to be changed. This will increase the material distribution deviation. In this paper, algorithms are developed to minimize the material distribution deviation because of the change of the spray width. The material distribution requirements can then be satisfied