Casting parts need to be subjected to the kind of heat treatment after the weldment is finished
1, gray cast iron: General graphite annealing, to be heat treatment annealing, surface hardening etc.; ductile iron can be various: annealing, normalizing, quenching and isothermal quenching, surface treatment, chemical heat treatment.2. Pouring liquid metal into the casting cavity which adapts to the shape of parts. After cooling and solidification, the casting method is called casting. Castings obtained by casting are called castings. Casting structure design: ensure the working performance and mechanical performance requirements, consider the technical requirements and performance of alloy casting casting casting structure, casting structure design is reasonable or not, the casting quality, productivity and cost has a great influence.3. Heat treatment is a metal hot working process in which the material is in solid state by means of heating, heat preservation and cooling to obtain desired microstructure and properties
Annealing is needed to eliminate stress and refine grain
This is difficult to say, the key is to see the specific parts and components, the final mechanical performance requirements.For example, gray cast iron, usually graphite annealing, to heat treatment annealing, surface quenching and so on, ductile iron can be a variety of annealing, normalizing, quenching and isothermal quenching, surface treatment, chemical treatment and so on, in a word, heat treatment of steel can usually, nodular cast iron can do. Malleable cast iron and vermicular cast iron are often subjected to graphitization annealing and stress relieving annealing, while wear-resistant cast irons often undergo quenching + low temperature tempering, and so on.Welding is the case, such as bearing steel welding must be quenched + low temperature tempering, machine spindle welding (repair welding) must be quenched and tempered treatment, and so on. Of course, if it is a general weld, there is no need for heat treatment or, at most, stress relieving annealing.
