本文關(guān)鍵詞： .CrMoV鋼 焊接粗晶熱影響區(qū) 熱模擬 再熱裂紋敏感性　出處：《機(jī)械工程學(xué)報》2015年06期 　論文類型：期刊論文

【摘要】：再熱開裂曾多次在2.25Cr1MoV鋼反應(yīng)器的焊接粗晶熱影響區(qū)(Coarse-grained heat affected zone,CGHAZ)部位發(fā)生,卻很少在"斜Y型坡口再熱裂紋試驗(yàn)"中出現(xiàn)。考慮兩者之間的熱輸入差異,通過Gleeble熱模擬試驗(yàn)研究熱輸入對2.25Cr1MoV鋼CGHAZ再熱裂紋敏感性的影響,并結(jié)合顯微組織觀察、硬度測定及斷口分析,討論熱輸入、組織和性能之間的關(guān)系。結(jié)果表明,在5~100 kJ/cm的熱輸入范圍內(nèi),CGHAZ的再熱裂紋敏感性隨熱輸入的升高而增大,當(dāng)熱輸入為35 k J/cm時,CGHAZ在675℃對再熱開裂"高度敏感",限制熱輸入在25 kJ/cm以內(nèi),將有效降低其再熱裂紋敏感性。綜合分析發(fā)現(xiàn),模擬CGHAZ的高溫塑性與其在高溫拉伸試驗(yàn)后硬度的變化規(guī)律之間存在良好的對應(yīng)關(guān)系。當(dāng)軟化現(xiàn)象發(fā)生時,拉伸試樣的斷裂模式為穿晶與沿晶的混合型斷裂,具有較高的斷面收縮率(Reduction of area,Ro A),當(dāng)二次硬化現(xiàn)象發(fā)生時,其斷裂模式為均一的微孔聚集型沿晶斷裂,RoA顯著降低。試驗(yàn)結(jié)果從二次硬化的角度反映了高熱輸入條件下CGHAZ的再熱脆化機(jī)理。
[Abstract]:Reheat cracking occurred many times in the coarse-grained heat affected zonezon CGHAZ site of the 2.25Cr1MoV steel reactor, but rarely in the "inclined Y groove reheat crack test". The effect of heat input on the sensitivity of CGHAZ reheat crack of 2.25Cr1MoV steel was studied by Gleeble thermal simulation test. The relationship among heat input, microstructure and properties was discussed by means of microstructure observation, hardness measurement and fracture analysis. The reheat crack sensitivity of CGHAZ increases with the increase of heat input in the heat input range of 5 ~ 100 kJ/cm. When the heat input is 35 kJ/cm, it is "highly sensitive" to reheat cracking at 675 鈩，

本文編號：1499837