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CVN(Charpy V-notch) toughness and grain size number of J55 grade oil casings produced by Baotou Iron and Steel Company did not meet the reiative standards in the past. 本文針對包鋼原來生產(chǎn)的J55石油套管沖擊韌性不足，晶粒粗大的問題開展研究。 etd.calis.edu.cn
The extra-cryogenic impact toughness and influence factors of the high-Mn austenitic steel are studied by means of the Charpy V-notch impact test and the SEM fractured appearance analysis. 本文通過在超低溫下的V型缺口夏比沖擊試驗和SEM斷口分析研究了高錳奧氏體鋼的沖擊韌性及其影響因素。