When the temperature exceeds 300-400 degrees C (the blue and brittle zone of steel) and reaches 700-800 degrees C, the casting can make plastic deformation, change the scale, shape and improve function to make the forming process of mechanical parts, workpieces, tools or s. When the temperature exceeds 300-400 C (the blue and brittle zone of steel), the deformation resistance will be reduced sharply and the deformation can be greatly improved. According to the different temperature areas, the casting can be divided into three forming temperature regions, such as cold forging, warm forging and hot forging, for the difference between the quality of the forging and the demand of the casting technology. There is no strict boundary between this region of temperature. Generally speaking, the casting is called hot forging in the region of recrystallized temperature, and the casting that is not heated at room temperature is called cold forging.
In cryogenic casting, the dimension of forging is very small. Less than 700 degrees C, the oxide scale is less, and the surface has no decarburization. Therefore, only the deformation energy can be obtained in the forming energy range, and cold forging can achieve excellent scale accuracy and surface finish. We only need to control temperature and smooth cooling, and warm forging below 700 degrees can achieve excellent accuracy. When hot forging, because deformation energy and deformation resistance are very small, it can cast large forgings with complex shape. To obtain high precision forgings, hot forging can be done in the 900-1000 temperature range. In addition, we should pay attention to improving the working environment of hot forging. The number of forging dies (hot forging 2-5 thousand, warm forging 1-2 million, cold forging 2-5 million) is shorter than other casting in other temperature fields, but the degree of freedom is large and the cost is low.
When the should be deformed and hardened during cold forging to make the forging die accept high load, it is necessary to use high strength forging die and use hard smooth film treatment to avoid wear and bond. In addition, in order to avoid billet cracks, center annealing is needed to ensure the deformation of demand. In order to maintain excellent smoothness, billet can be phosphating. During continuous processing with rod and wire rod, the section can not be smoothed at present. The possibility of applying phosphating smoothing method is being studied.
Qingdao Hongtengda Machinery Manufacturing Co., Ltd. is a professional manufacturer, designer and exporter with ISO9001:2008 and ISO/TS 16949:2002 quality systems, engaging in forging part、Auto Forging and rigging.
Our products have good mechanical properties after forging, normalization,cold coining,shot blast and rust proof.Moreover,the field quality controllers have carry out the QC standard do thetimed sampling inspection,which ensures our forging parts have stable quality. Welcome to send drawing or send drawing or sample to inquiry us.