Dear İlke Bengi ;

The powder is made by atomisation in an inert gas; the extent of chemical segregation cannot exceed the size of the powder. After atomisation, Some discs are made from powder which is hot-isostatically pressed, extruded and then forged into the required shape. The process is difficult because of the need to avoid undesired particles being introduced, for example, from the refractories used in the atomisation process, or impurities picked up during solidification. Such particles initiate fatigue and of course, the failure of an aero-engine turbine disc can be catastrophic. more details in the references;

• https://www.totalmateria.com/page.aspx?ID=CheckArticle&site=ktn&NM=259
• https://link.springer.com/article/10.1007/s11837-999-0005-y
• https://www.sciencedirect.com/topics/materials-science/nickel-based-superalloys

Development of advanced P/M Ni-base superalloys for turbine disks

• DOI: 10.1051/matecconf/20141417001

Thank you