1: casting (castability) : refers to metal materials with the performance of the casting method to obtain qualified castings.Casting mainly include liquidity, shrinkage and segregation.Liquidity refers to the liquid metal mold ability, contractility refers to the casting solidification, the extent of the volume contraction, segregation is refers to the metal in the process of cooling solidification, caused by different crystallization has internal metal chemical composition and non-uniformity of the organization.
2: forgeability: refers to the metal material processing, the pressure can change shape without crack performance.It includes under hot or cold to hammer forging, rolling, extrusion, extrusion processing, etc.The stand or fall of malleability mainly related to the chemical composition of metal materials.
3: cutting machining (cutting, machinability) : refers to metal materials and become qualified after being cutting tool machining of artifacts.Commonly used cutting machining is good or bad after processing the surface roughness of the workpiece, allowed to measure the cutting speed and tool wear degree.It and the chemical composition of metal materials, mechanical properties, thermal conductivity and the degree of strain hardening and so on many factors.Hardness and toughness is usually use for cutting machining is good or bad idea.Generally speaking, the higher the hardness of metal material and harder cutting, hardness is not tall, but great toughness, cutting is also more difficult.
4: weldability (weldability) : refers to the metal material of the welding process of adaptive performance.Mainly refers to the welding process under certain conditions, access to quality to the difficulty of the welded joint.It includes two aspects of content: one is the combination of performance, namely under the condition of certain welding process, the sensitivity of certain metal forming welding defect, 2 it is to use performance, namely under the condition of certain welding process, requirements of the use of certain metal welded joint of applicability.
5: heat treatment
(1): annealing: refers to the metal material of heating to proper temperature, keep a certain amount of time, and then slowly cooling heat treatment process.Common annealing process has: recrystallization annealing, the stress relieving, spheroidizing annealing and full annealing, etc.Annealing: the purpose of the main is to reduce the hardness of metal materials, improve the plasticity, processing and machining and pressure, and reduce the residual stress, improve the organization and composition of the homogenization, or for the heat treatment after ready for the organization, etc.
(2) : normalizing refers to heat the steel or steel to a Ac3 or Acm (steel) on the critical point of temperature more than 30 ~ 50 ℃, keep proper time, in the stillness of the air cooling heat treatment process.: the purpose of normalizing the main is to improve the mechanical properties of low carbon steel, improve the cutting processability, refine the grain size, remove the tissue defects, such as heat treatment after ready for the organization.
(3) : quenching refers to heat the steel to the Ac3 or Ac1 point temperature (steel) above a certain temperature, keep a certain amount of time, and then in the appropriate cooling speed, get martensite bainite) (or heat treatment process of the organization.Common salt bath quenching, quenching process are martensite interrupted quenching, bainite isothermal quenching, surface hardening and selective hardening, etc.Steel quenching purpose: to get the required martensite structure, improve the hardness, strength and wear resistance, such as heat treatment after ready for the organization.
(4) : tempering: refers to the steel after hardening, and then heated to Ac1 under a certain temperature, heat preservation time, and then cooled to room temperature of heat treatment process.Common tempering process are: low temperature tempering, the tempering temperature, high temperature tempering, and multiple tempering, etc.Tempering purpose: mainly to eliminate steel produced during quenching stress, the steel with high hardness and wear resistance, and with desired plasticity and toughness, etc.
(5) : conditioning: refers to the steel or composite steel quenching and tempering heat treatment process.The conditioning treatment used in steel quenched and tempered steel.It usually refers to the carbon structural steel and medium carbon alloy steel.
(6) : chemical heat treatment: refers to the metal or alloy workpiece under a certain temperature in the active medium heat preservation, make one or more of the following elements into its surface, to change its chemical composition, microstructure and properties of heat treatment process.Common chemical heat treatment process are: carburizing, nitriding, carbonitriding, aluminized, boronizing, etc.The purpose of chemical heat treatment: the main is to improve the hardness of the steel surface, wear resistance, corrosion resistance, fatigue resistance and oxidation resistance, etc.
(7) : solid solution treatment: refers to the area will be heated to high temperature alloy single-phase constant temperature keeping, the excess phase dissolves into solid solution after rapid cooling, to get the supersaturated solid solution heat treatment process.The purpose of solid solution treatment: the main is to improve the plasticity and toughness of steel and alloy, to prepare for precipitation hardening treatment, etc.
(8) : precipitation hardening (precipitation strengthening) : refers to the metal in the supersaturated solid solution of solute atom partial area and (or) by exsolution of the particles are dispersed in the matrix and lead to a heat treatment hardening.Such as precipitation austenitic stainless steel after solid solution treatment or after cold working, in 400 ~ 500 ℃ or 500 ~ 700 ℃ for precipitation hardening treatment, high strength can be obtained.