發(fā)布時間：2018-05-06 08:25

  本文選題：金屬材料 + 高溫力學性能��； 參考：《機械工程學報》2017年06期

【摘要】：針對鑄輾連續(xù)成形工藝中高溫出模環(huán)形鑄坯的易裂缺陷,采用Gleeble-3500熱力模擬試驗機對鑄造42CrMo鋼環(huán)坯進行高溫拉伸試驗,分析其高溫強度、熱塑性等力學行為,預測高溫易裂敏感溫度區(qū)。結果表明:鑄造42CrMo鋼的抗拉強度隨溫度的升高及應變速率的減小而減小。斷面收縮率隨應變速率增大而增大。1 100℃時,試樣開始發(fā)生動態(tài)再結晶。試驗條件下,材料存在兩個脆性溫度區(qū),分別為紅脆性溫度區(qū)和高溫脆性溫度區(qū)。高溫脆性是導致鑄造42CrMo高溫出模環(huán)坯產生裂紋的內在原因。能譜分析表明:硫化物、氧化物等夾雜物極易誘發(fā)裂紋的發(fā)生。根據(jù)試驗結果,建立鑄造42CrMo鋼的峰值流動應力模型及產生裂紋的臨界應變模型,該模型可為優(yōu)化鑄輾連續(xù)成形工藝,避免鑄造缺陷,提高鑄件質量提供指導。
[Abstract]:In view of the easy cracking defects of ring billet produced by high temperature die in continuous casting rolling process, the high temperature tensile test of cast 42CrMo steel ring billet was carried out by using Gleeble-3500 thermal simulation machine, and the mechanical behaviors such as high temperature strength, thermoplasticity and so on were analyzed. The sensitive temperature region of high temperature cracking is predicted. The results show that the tensile strength of cast 42CrMo steel decreases with the increase of temperature and the decrease of strain rate. Dynamic recrystallization occurs when the cross section shrinkage rate increases with strain rate increasing at 1.100 鈩，

本文編號：1851535