公开(公告)号：US5529643A

公开(公告)日：1996-06-25

申请号：US323969

申请日：1994-10-17

申请人： Duk Y. Yoon ,  Aldo E. Murut ,  Michael F. Henry ,  Renee M. Rohling ,  Charles P. Blankenship ,  Mark G. Benz ,  Edward L. Raymond ,  Eric S. Huron

发明人： Duk Y. Yoon ,  Aldo E. Murut ,  Michael F. Henry ,  Renee M. Rohling ,  Charles P. Blankenship ,  Mark G. Benz ,  Edward L. Raymond ,  Eric S. Huron

IPC分类号： C22F1/10

CPC分类号： C22F1/10

摘要： A method is provided for obtaining uniform grain growth within .gamma.' precipitation strengthened nickel-base superalloys. The method includes forming a billet having a very fine grain size in order to achieve optimum superplasticity of the superalloy during forging. The article is then heated to a pre-working hold temperature in a manner which prevents coarsening of the microstructure and a loss of superplasticity. The article is then worked, such as by forging, at a temperature below the .gamma.' solvus temperature of the alloy, so as to maintain local strain rates within the article below a critical strain rate for random grain growth, and so as to maintain the strain rate gradient throughout the article below a critical upper limit. After working, the article is subjected to annealing at a temperature which is less than the .gamma.' solvus temperature of the alloy, and for a duration which is sufficient to remove accumulated metallurgical strain in the article. A supersolvus heat treatment is then performed by further heating the article to a temperature above the .GAMMA.' solvus temperature of the superalloy for a duration sufficient to uniformly coarsen the grains of the article.

摘要翻译： 提供了一种在γ'沉淀强化镍基超级合金中获得均匀晶粒生长的方法。 该方法包括形成具有非常细晶粒度的坯料，以便在锻造期间达到超合金的最佳超塑性。 然后将制品以防止微结构粗化和超塑性损失的方式加热到预加工保持温度。 然后将该制品例如通过锻造在低于合金的γ'固溶温度的温度下加工，以使得该制品内的局部应变速率低于随机晶粒生长的临界应变速率，并且保持 整个制品的应变速率梯度低于临界上限。 加工后，制品在比合金的γ'溶解温度低的温度下进行退火，持续时间足以清除制品中累积的冶金应变。 然后通过将制品进一步加热到超过合金的GAMMA'solvus温度的温度持续足以均匀地粗化制品的颗粒的时间来进行超溶解热处理。