Jiangyin Hengye Forging Co., Ltd
How much does a large forging cost? Some knowledge points of forgings
What is the price of large forgings? Forgings refer to workpieces or blanks obtained by forging and deforming metal blanks. The mechanical properties of the metal blank can be altered by applying pressure to the metal blank to produce plastic deformation. According to the temperature of the billet during processing, forgings can be divided into cold forging, warm forging and hot forging. Cold forging is generally processed at room temperature, while hot forging is processed at temperatures above the recrystallization temperature of the metal blank.
Price of large forgings
What is the price of large forgings? Forgings in the quenched state have the following three main characteristics. Microstructure characteristics: According to forging size, heating temperature, time, transformation characteristics and cooling method, the quenched microstructure of forgings is mainly composed of martensite or martensite plus retained austenite, and there may be some undissolved carbonization thing. Martensite and retained austenite are metastable at room temperature, and both have a tendency to transform into a stable state of iron ingot and cementite.
What is the price of large forgings? Hardness of forgings: The lattice distortion caused by carbon atoms is expressed by hardness, and the hardness increases with the increase of supersaturation (ie, carbon content). The quenched structure has high hardness and strength, but low plasticity and toughness.
Stress characteristics of forgings: including micro-stress and macro-stress. The former is related to the lattice distortion caused by carbon atoms, especially the larger value of martensite in high carbon, indicating that martensite is in a state of strong stress during quenching. The latter is caused by the temperature difference formed on the cross section during quenching. The different stress states on the surface or center of the workpiece, including tensile or compressive stress, keep the inside of the workpiece balanced. If the internal stress of quenched forgings is not eliminated in time, the parts will be further deformed or even cracked.
What is the price of large forgings? To sum up, although the workpiece after quenching has high hardness and high strength, it needs to be large, the structure is unstable, and the internal stress of quenching is large, so it must be tempered before it can be used. Generally speaking, the tempering process is an indispensable follow-up process after the forging is quenched, and it is also the last process of the heat treatment process, giving the workpiece the required properties.
What is the price of large forgings? Tempering is a heat treatment process in which the quenched steel is heated to a certain temperature below a certain value, kept for a certain period of time, and then cooled to room temperature. Its main purposes are: to adjust the hardness and strength of the steel reasonably, to improve the toughness of the steel, and to make the workpiece meet the requirements of use; structural stability, so that the structure of the workpiece will not change during long-term use, thereby stabilizing the shape and size of the workpiece; Or reduce the quenching internal stress of the forging to reduce the deformation of the workpiece and prevent cracking.
When the workpiece is quenched, tempered, annealed and normalized, the hardness is less than 45HRC. Cutting has little effect on the quality of the workpiece, including surface finish, residual stress, machining allowance, and removal of decarburized and carbon-depleted layers on the surface. so as not to alter the underlying performance of the workpiece.
What is the price of large forgings? Hardened steel or workpiece processing, also known as hard processing, has a hardness of up to 50~65HRC. Materials mainly include ordinary quenched steel, quenched die steel, bearing steel, rolled matt steel and high-speed steel. The influence of cutting is obvious. The generation and conduction of cutting heat, high-speed friction and wear during the cutting process will cause certain damage to the machined surface. The integrity of the hard machined surface mainly includes surface morphology, hardness, surface roughness, dimensional accuracy, residual stress distribution and the generation of white layer. The hardness of the machined surface increases with increasing cutting speed and decreases with increasing feed. In addition, the higher the hardness of the machined surface, the greater the depth of the hardened layer. The results show that the residual compressive stress on the workpiece surface after hard cutting is uniform, while the larger compressive stress on the workpiece after grinding is mainly concentrated on the surface of the forging.