The quality of the titanium plate is largely determined by the smelting process, including the chemical composition of titanium, the cleanliness of titanium water (gases, harmful elements, inclusions) and the quality of the slab (segregation of components, decarburization and surface conditions) These aspects are the key control points for smelting operations. In addition, industrial titanium plates also require sufficient hardenability to ensure uniform microstructure and mechanical properties throughout the spring section. The main cause of fatigue cracks is the inclusion of oxides in titanium, and Class D inclusions are more harmful to fatigue life than Class B inclusions. Therefore, foreign titanium factories and automobile factories have put forward higher requirements for oxide inclusions in industrial titanium plates. For example, the Swedish SKF standard requires that the oxygen content in titanium is less than 15×10-6, and class D inclusions are lower than class B inclusions. Thing. In particular, the inclusions of Al2O3 and TiN are the most harmful to the fatigue life of titanium springs. In order to produce high-quality industrial titanium plates, special smelting methods such as electric furnace-electroslag remelting or vacuum arc remelting are usually used in the past. Forging of titanium plate blanks is usually used to produce products with similar shapes and dimensions, followed by heat treatment and cutting. The final rough. The casting temperature and the degree of deformation are the fundamental factors that determine the arrangement and function of the titanium alloy. The heat treatment of the titanium plate blank products factory is different from the heat treatment of steel, and it has no resolution effect on the arrangement of titanium alloys. Therefore, the process standard of the final step of forging of titanium plate blank products factory has unique and important effects. In order to make the die forgings of the titanium plate blank products factory achieve higher strength and plasticity together, it is necessary to make the overall deformation of the blank not less than 30%, the deformation temperature does not exceed the phase transition temperature, and the temperature and deformation degree should be determined throughout The deformed blank can be evenly distributed as much as possible. Titanium plate rough products factory die forging arrangement and functional uniformity stainless steel forgings. In the violent metal activity area, after recrystallization heat treatment, the low magnification is ambiguous crystals, and the high magnification is equiaxed fine crystals; in the hard deformation area, due to the small amount of deformation or no deformation, the arrangement often saves the state before deformation. Therefore, in the forging of some important titanium plate blank products factory parts (such as compressor disks, blades, etc.), in addition to controlling the deformation temperature below TB and the appropriate degree of deformation, the arrangement of controlling the original blank is very important, otherwise, The coarse grain arrangement or some shortcomings will be inherited into the forging, and the subsequent heat treatment cannot be eliminated, which will cause the forging to be scrapped.
When the closed die forging method is adopted to process forged titanium plate blank products, the life of the die is reduced because of the high pressure. Therefore, closed die forging must strictly limit the volume of the original blank, which complicates the preparation process. Whether to choose closed die forging depends on both cost and process feasibility. In the open die forging, the burr loss accounts for 15% to 20% of the blank component, and some process scraps (if necessary according to the die forging conditions) must be held for 10% of the blank component. Relative loss of burr metal is usually added as the blank component is reduced. For some asymmetry layouts, large cross-sectional area differences, and some forgings that are difficult to fill, the burr cost can be as high as 50%. Although there is no burr loss in closed die forging, but the blank making process is messy, it is necessary to add more transitional grooves, which will undoubtedly add auxiliary costs.
The reaction layer on the surface of the titanium plate is the main factor that affects the physical properties of the titanium plate. After the titanium plate is rolled, it needs to be annealed. The oxide layer generated by the titanium plate needs to be removed by the method of explosive alkaline pickling to remove the surface reaction layer of the titanium plate.
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