Production of Die-Forged Discs from BT9 Alloy Powder
It is well known that one of the problems connected with the production of a homogeneous structure with good properties is to remove segregation associated with a cast structure. Increased productivity and reduced initial cost of the product calls for the use of high-capacity equipment and consequently leads to an increase in ingot size. However, an increased ingot diameter leads to increased heterogeneity of chemical composition, due to the processes of solidification and segregation and associated increased grain size and coarser second phases. Despite the fact that an increase in the ingot size results in an increase in the total reduction accompanying the fabrication of a given type of semi-finished product, the casting defects of a large-size ingot are generally liable to affect the product quality. The use of a powder approach eliminates completely the problem of segregation and coarse phases, since the as-cast powder structure may be optimum. It is formed in conditions of high solidification and cooling rates and results in homogeneous properties (Fig. 1). In addition, the fabrication of products from titanium alloys using the powder metallurgy approach makes it possible to reduce cost due to a lower labor consumption and higher output.
KeywordsCompaction Temperature Interstitial Content Diffusion Welding Coarse Phasis Rotate Electrode Process
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