中国有色金属学报
中國有色金屬學報
중국유색금속학보
THE CHINESE JOURNAL OF NONFERROUS METALS
2013年
10期
2808-2816
,共9页
肖旋%高慈%秦学智%郭永安%郭建亭%周兰章
肖鏇%高慈%秦學智%郭永安%郭建亭%週蘭章
초선%고자%진학지%곽영안%곽건정%주란장
DZ483高温合金%定向凝固%抽拉速率%微观组织%持久性能
DZ483高溫閤金%定嚮凝固%抽拉速率%微觀組織%持久性能
DZ483고온합금%정향응고%추랍속솔%미관조직%지구성능
DZ483 superalloy%directional solidification%withdrawal rate%microstructure%creep properties
研究抽拉速率对DZ483合金微观组织及力学性能的影响。结果表明:随着抽拉速率的提高,合金的一、二次枝晶间距逐渐减小,γ′相尺寸减小,但γ′相的数量增多;共晶组织及枝晶间碳化物的数量增多。碳化物形貌由块状转变成长条状,类型不随抽拉速率的提高而改变。随着抽拉速率的升高,除Cr元素偏析系数在1左右波动外,其余元素的偏析程度都增加,其中W、Mo元素偏析程度明显加重;DZ483合金的持久性能随抽拉速率的提高先升高后降低。不同抽拉速率下,合金断口均呈现出韧性断裂和脆性断裂混合特征,γ′相为合金的主要强化相。随着抽拉速率的提高,一方面,合金中γ′相的数量逐渐增多,尺寸逐渐减小,提高了合金的持久性能;另一方面,由于元素偏析程度加重、碳化物和共晶数量增多及γ′相筏形化规则程度的下降,降低了合金的持久性能。
研究抽拉速率對DZ483閤金微觀組織及力學性能的影響。結果錶明:隨著抽拉速率的提高,閤金的一、二次枝晶間距逐漸減小,γ′相呎吋減小,但γ′相的數量增多;共晶組織及枝晶間碳化物的數量增多。碳化物形貌由塊狀轉變成長條狀,類型不隨抽拉速率的提高而改變。隨著抽拉速率的升高,除Cr元素偏析繫數在1左右波動外,其餘元素的偏析程度都增加,其中W、Mo元素偏析程度明顯加重;DZ483閤金的持久性能隨抽拉速率的提高先升高後降低。不同抽拉速率下,閤金斷口均呈現齣韌性斷裂和脆性斷裂混閤特徵,γ′相為閤金的主要彊化相。隨著抽拉速率的提高,一方麵,閤金中γ′相的數量逐漸增多,呎吋逐漸減小,提高瞭閤金的持久性能;另一方麵,由于元素偏析程度加重、碳化物和共晶數量增多及γ′相筏形化規則程度的下降,降低瞭閤金的持久性能。
연구추랍속솔대DZ483합금미관조직급역학성능적영향。결과표명:수착추랍속솔적제고,합금적일、이차지정간거축점감소,γ′상척촌감소,단γ′상적수량증다;공정조직급지정간탄화물적수량증다。탄화물형모유괴상전변성장조상,류형불수추랍속솔적제고이개변。수착추랍속솔적승고,제Cr원소편석계수재1좌우파동외,기여원소적편석정도도증가,기중W、Mo원소편석정도명현가중;DZ483합금적지구성능수추랍속솔적제고선승고후강저。불동추랍속솔하,합금단구균정현출인성단렬화취성단렬혼합특정,γ′상위합금적주요강화상。수착추랍속솔적제고,일방면,합금중γ′상적수량축점증다,척촌축점감소,제고료합금적지구성능;령일방면,유우원소편석정도가중、탄화물화공정수량증다급γ′상벌형화규칙정도적하강,강저료합금적지구성능。
The effects of withdrawal rate on the microstructure and mechanical properties of directionally solidified DZ483 superalloy were investigated. The results show that, with the withdrawal rate increasing, both the primary and secondary dendrite arm spacing decrease gradually, and the size ofγ′precipitates decreases, but the quantity ofγ′phase increases obviously. The number of eutectic and carbides within the interdendritic region increases. However, the morphology of carbides transforms from blocky into strip-like. Except the Cr element with segregation coefficient of about 1, the segregation of the elements becomes worse with the increase of the withdrawal rate, especially W and Mo. With the increase of the withdrawal rate, the stress rupture life of the alloy increases initially and then decreases. The main fractographic appearance is brittle and tough at different withdrawal rates. With the withdrawal rate increasing, on the one hand, the size ofγ′precipitates decreases, and the quantity increases, which improves the stress-rupture properties. On the other hand, stress-rupture properties of superalloy worsen because of the increase of element segregation, the increase of the number ofγ/γ′eutectic structure and carbides, and the decrease of the irregular morphology ofγ′rafting.