Malleability refers to the ability of forging metal materials to change shape without cracking during pressure machining. Including in hot or cold state can be forging, rolling, stretching, extrusion and other processing. Malleability is actually a performance of the plastic quality of forging metal material, mainly related to the chemical composition of forging metal material.
weldability
Weldability refers to the forging metal in particular structure and process conditions through conventional welding method to obtain the expected quality requirements of the performance of the welding joint, generally speaking, the thermal conductivity is too high or too low, thermal expansion, low plasticity or welding easy oxidation, suction metal, the weldability is poor. Low carbon steel forgings have good weldability, medium carbon steel forgings have medium weldability, high carbon steel, high alloy steel, cast iron and aluminum alloy have poor weldability.
Machinability
Machinability refers to the difficulty of forging metal materials after cutting to meet the requirements of the workpiece. The cutting machinability is measured by the surface roughness of the workpiece, the allowable cutting speed and the wear degree of the tool. It is concerned with a lot of factors such as the chemical composition, mechanical properties, thermal conductivity and degree of work hardening of metallic materials. Forgings usually use hardness and toughness as the rough index of cutting machinability. Generally speaking, the higher the hardness of metal materials, the more difficult it is to cut. Although the hardness is not high, the hardness is large, and the cutting is more difficult. Non-ferrous metals have better machinability than ferrous materials, cast iron has better machinability than steel, and medium carbon steel has better machinability than low carbon steel.
Heat treatment technicality
Refers to forging or heat treatment alloy within the scope of the solid state, through a certain heating, heat preservation and cooling methods, so as to change the internal organization of metal or alloy and get the required performance of a heat treatment craft operation refers to the metal after heat treatment, the microstructure and property change ability, including the hardenability, hardenability and temper brittleness, oxidation and decarbonization trend, etc.