304不銹鋼高溫加工特性研究與應用

Hot Workability of Type 304 Stainless Steel

潘永村(Yeong-Tsuen Pan) ； 李至隆(Jye-Long Lee)

《鑛冶：中國鑛冶工程學會會刊》 40卷2期 (1996/06) Pp. 95-106+28

https://doi.org/10.30069/MM.199606_40(2).0010

摘要

不銹鋼因含高於11.5%的鉻，故擁有良好的耐蝕性，但也因其合金含量過高，使其在高溫加工成形時，容易出現成形負荷過大或工件破裂等問題，使產率大幅降低。本研究之主要目的為探討成份及加工製程參數對304不銹鋼的高溫變形阻抗及高溫延性之影響，以做為加工製程設定之參考。在變形阻抗方面，可發現其隨變形溫度降低及變形速率增加而增加；熱加工時發生軟化所需之活化能為431 kJ/mol.。在高溫延性方面，當304不銹鋼之硫含量過高或含有太多的肥粒鐵均會使其延性急劇下降。在沃斯田鐵相域內加熱，304不銹鋼之肥粒鐵含量隨肥粒鐵生成指標（δcal）之提高，加熱溫度降低與時間縮短而增加。應用本研究之結果降低硫含量，控制肥粒鐵生成指標，並配合適當之再加熱條件，可提升304不銹鋼之高溫延性，使邊裂發生率大幅降低。

關鍵字

沃斯因鐵系不銹鋼 ； 熱加工性 ； 變形阻抗 ； 熱延性

並列摘要

Stainless steels possess very good corrosion resistance because they usually contain Cr content over 11.5%. The high alloying content of stainless steels, however, causes overloading and cracking during hot working, and thus significantly decreases the production yield. The aim of this study is to investigate the effects of composition and deformation parameters on the hot workability (deformation resistance and hot ductility) of type 304 stainless steel (S. S.). The deformation resistance of type 304 S. S. increases with decreasing temperature and increasing strain rate. The activation energy for dynamic restoration of 304 S. S. is about 431 KJ/mol.. The hot ductility of 304 S. S. decreases with increasing content of sulphur and the amount of delta ferrite. When 304 S. S. was reheated in the austenite region, the amount of ferrite increase s with increasing ferrite index and decreasing temperature and holding time. A significant improvement of edge cracking problem is achieved by lowering the sulphur content, controlling the ferrite index, and selecting optimum reo heating conditions, which contribute to the increase of hot ductility of 304 S. S..

並列關鍵字

Austenitic stainless steel ； Hot corrkability ； Deformation resistance ； Hot ductility