鐵-15.5鉻-4.5鎳-3鉬-1錳-0.1碳合金球化處理對機械性質之影響

Effect of Spheroid on the Mechanical Properties of Fe-15.5Cr-4.5Ni-3Mo-1Mn-0.1C Alloy

沈宗樺

指導教授 ： 趙志燁

國立屏東科技大學/工學院/機械工程系所/碩士(2010年)

https://doi.org/10.6346/NPUST.2010.00229

摘要

本研究是利用掃描式電子顯微鏡(SEM)、X光繞射儀(XRD)及拉伸試驗機等器材，探討鐵-15.5鉻-4.5鎳-3鉬-1錳-0.1碳合金之相變化及機械性質，主要研究結果如下：
鐵-15.5鉻-4.5鎳-3鉬-1錳-0.1碳合金經830℃固溶1H深冷-80℃/8H+時效480℃/4H，發現基地內碳析出產生碳化物，Ms溫度上昇，組織結構全部轉換為麻田散鐵，時效後機械性質，抗拉強度1564~1598MPa降伏強度1336~1350MPa，延伸率為7%~8%。在980℃固溶1H深冷-80℃/8H+時效處理480℃/4H，其顯微結構組織為碳從基地析出，造成麻田散鐵變態溫度Ms下降，殘留沃斯田鐵球化增多，時效後其機械性質抗拉強度1474~1488MPa與降伏強度1247~1260MPa延伸率15%~17%。在抗拉強度微微降低，降伏強度變化不大，本實驗以不同冷卻方式產生的沃斯田鐵球化比例也不同，在液態氮冷卻時，產生球化沃斯田鐵相比例是最高。

關鍵字

不銹鋼 ； 球化沃斯田鐵 ； 延伸率

並列摘要

The purposes of the present studies are to investigate the microstructures and mechanical properties of the commercial Fe-15.5Cr-4.5Ni-3Mo-1Mn-0.1C alloy stainless steel by using of the SEM, XRD and tensile tests. Some results are described as following:
Being solution, sub-zero, and ages heated treatment, the microstructure of the commercial Fe-15.5Cr-4.5Ni-3Mo-1Mn-0.1C alloy stainless steel is a mixture of the tempered martensite and austenite phases. In general, the UTS, YS, and EL of the present alloy are in the ranges of 1485~1495 MPa, 1254~1267 MPa, and 8~10％, respectively. Based on the present studies, Fe-15.5Cr-4.5Ni-3Mo-1Mn-0.1C alloy were heated at 980℃ resulting to the austenite being spheroid. In addition, the elongation of the Fe-15.5Cr-4.5Ni-3Mo-1Mn-0.1C alloy would be increased to 15~17% with imperceptible decreased the UTS. Moreover, increasing the cooling rate, the amount of the spheroid austenite would increase.
Keyword: spheroid, austenite, elongation

參考文獻

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