Seal a head to metal blank (do not contain plate) bring to bear on outside force, make its produce plasticity to be out of shape, change dimension, appearance and improvement function, in order to produces the form cutting method of mechanical spare parts, workpiece, tool or semifinished product. Forginging sort and characteristic exceed 300-400 ℃ when temperature (the) of blue fragile area of steel, when achieving 700-800 ℃ , be out of shape instruction will be reduced quickly, be out of shape also can get very big improvement. Forging according to be in what different temperature area undertakes, mix in the light of forging quality forging what craft asks is different, can divide for cold forging, lukewarm forge, hot forge 3 shape temperature area. Originally of area of this kind of temperature differentiate and do not have strict limit, popularly is told, forging in what have the temperature area of recrystallization forge calling heat, do not heat to forging in what room temperature falls call cold forging. When microtherm forgings, the dimension change of forging is very little. Stainless steel seals a head to forging below in 700 ℃ , oxidation skin is formed little, and the surface does not have decarbonization phenomenon. Accordingly, should be out of shape only can be in figuration can inside limits, cold forging gets very good dimension precision and face easily bright and clean degree. Want to control good temperature and lubricant refrigeration only, the lukewarm whorl pipe fitting under 700 ℃ , to solder pipe fitting, forge of stainless steel pipe fitting also can obtain very good precision. When hot forge, because be out of shape,can mix be out of shape resistance is very little, can forging the big forging with complex form. Want to get the forging of expensive measure precision, the treatment that heat up forge can be used inside region of 900-1000 ℃ temperature. Additional, the working environment that should notice improvement heats up forge. Forging die life (hot forge 2-5 1000, lukewarm forge 1-2 10 thousand, cold forging 2-5 10 thousand) with other temperature region forginging to be compared is shorter, but its freedom is spent big, cost is low. Preform wants to generation is out of shape and machine sclerosis when cold forging, make forging die bears high load, accordingly, the forging die that needs use high strength and use prevent to wear away the processing technique of horniness lubricating film with felt. Additional, to avoid preform flaw, intermediate anneal makes need in order to assure when need be out of shape ability. To hold good lubricant position, stainless steel seals a head to be able to undertake to preform phosphor changes processing. When the makings that use a stick and wire rod have successive treatment, still cannot make lubricant processing to section at present, studying use phosphor changes the likelihood of method of lubrication. According to the mobile means of preform, forging can divide for free forge, Dui forge of the thick, extruding, die forging, die forging that shut type, Dui that shut type. Because the die forging that shut type and forge of the Dui that shut type do not have flash, the utilization rate of material is high. Complete the precision work of complex forging possibly with a working procedure or a few working procedure. Because do not have flash, the area getting power of forging decreases, needs load also decreases. But, should notice to cannot make preform is restricted completely, want to control the bulk of preform strictly for this, the opposite niche that dominates forging die and undertake metrical to forging, reduce forging die hard wear away. According to the athletic way of forging die, forging to be able to be divided again to place Zhan, place horizontal make friends of forge coming back, roller forge, wedge, stainless steel to seal the means such as head Zhan annulus and inclined make friends. Place Zhan, place forge coming back and Zhan annulus to also can use treatment of forge of essence of life. To raise the utilization rate of material, working procedure of the line before roller forge and horizontal make friends can use those who make long and thin material is machined. The whirl like free forge forgings also is local figuration, its advantage is with forging dimension photograph is compared, forging force also can come true below lesser circumstance form. Include free forge inside this kind forgings means, the material when treatment from the mould expand to free surface near the face, accordingly, assure precision very hard, so, calculate the athletic way of forging die and maneuver of foreword of forging coming back engine control, usable and inferior forging force wins figure the product with complex, expensive precision. Manufacture variety for example the forging such as the turbine lamina with much, large size. CNC Milling
