采用V K‐9710型激光共聚焦显微镜对热浸镀铝球墨铸铁试样的三点弯曲失效过程进行原位观察，分析镀层和基体的裂纹萌生和扩展机理。结果表明：对于纯Al浸镀球墨铸铁，在拉应力作用下，铁铝合金镀层率先萌生裂纹，诱导临近基体中铁素体撕裂与石墨球剥离，裂纹近似垂直于拉应力方向并沿着临近石墨球最短途径扩展；压应力导致表面纯Al层剥离和铁铝合金层破碎，镀层失效对球墨铸铁基体基本无影响。对于Al‐3．7Si‐1．0RE浸镀球墨铸铁，拉应力作用下的失效机理与纯Al浸镀相似；压应力作用下纯Al层和铁铝合金层与基体脱开，表现为铁素体基体失效。
Using laser scanning confocal microscope ,failure process of aluminized ductile iron samples w ere in‐situ observed during three‐point bending test ,w hile crack initiation and propagation mecha‐nism were analyzed in the area of coating and matrix .The results show that for hot‐dipped samples in Al ,cracks mainly initiate in the Fe‐Al alloy coating under tensile stress ,then induce the tearing of ferrite and the peeling of graphite in the adjacent matrix .T hereby cracks spread to the inner matrix in shortest route between graphite and ferrite ,in the direction nearly vertical to tensile stress .In case of compression stress ,aluminized alloy layer is crushed and aluminum layer is peeled off ,w hich having little influence on the failure of matrix .For hot‐dipped samples in Al‐3 .7Si‐1 .0RE ,failure mechanism under tensile stress is similar to that of hot‐dipped samples in Al ;under compression stress ,alumi‐num and Fe‐Al alloy coatings are disengaged from matrix ,exhibits failure occurring in the ferrite ma‐t rix .
参考文献
| [1] | 王德庆;于金龙;段旭东.钢铁表面热浸镀铝技术回顾[J].大连铁道学院学报,2003(3):77-83. |
| [2] | 刘洪福;牛宗伟;赵东山.热浸镀铝技术研究进展与展望[J].全面腐蚀控制,2011(11):11-14. |
| [3] | 张伟;刘爱萍;文九巴.镀铝温度对渗铝层/基体界面空洞生长动力学的影响[J].材料热处理学报,2012(4):127-131. |
| [4] | 孙伟;蔡启舟;罗强;何剑;顾佳婧.扩散退火对热浸镀铝层组织与抗高温氧化性的影响[J].材料热处理学报,2011(1):114-120. |
| [5] | 张伟;范志康;郭献军.热浸镀铝钢渗铝层的微观组织及其形成机理研究现状[J].机械工程材料,2006(1):9-11,55. |
| [6] | Sung-Ha Hwang;Jin-Hwa Song;Yong-Suk Kim.Effects of carbon content of carbon steel on its dissolution into a molten aluminum alloy[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,20051/2(1/2):437-443. |
| [7] | T. SASAKI;T. YAKOU;K. MOCHIDUKI.Effects of carbon contents in steels on alloy layer growth during hot-dip aluminum coating[J].ISIJ International,200512(12):1887-1892. |
| [8] | Cheng, WJ;Wang, CJ.Growth of intermetallic layer in the aluminide mild steel during hot-dipping[J].Surface & Coatings Technology,20096/7(6/7):824-828. |
| [9] | Wei-Jen Cheng;Chaur-Jeng Wang.Effect of silicon on the formation of intermetallic phases in aluminide coating on mild steel[J].Intermetallics,201110(10):1455-1460. |
| [10] | 宋世崑;刘顺华;高洪吾;王桂芹;周文龙.热浸镀铝钢丝组织和性能的研究[J].机械工程材料,2002(2):17-19,25. |
| [11] | 程乾;黄兴民;戴光泽.热浸镀铝球墨铸铁的耐蚀性能和冲击韧性[J].材料热处理学报,2014(2):157-163. |
| [12] | 钱庆生;李海;王芝秀;王秀丽;史志欣.HP40Nb钢热浸镀Al-Si高温氧化行为及组织研究[J].材料工程,2011(8):52-57. |
| [13] | 张伟;范志康;郭献军;文九巴;张金民.稀土对热浸镀铝钢Al2O3/渗铝层界面空洞生长的影响[J].航空材料学报,2006(2):16-19. |
| [14] | 张伟;陈冬梅.热浸镀镧铝钢的高温耐热行为研究[J].材料工程,2008(7):51-54. |
| [15] | Wang, M.;Wang, J.;Feng, H.;Ke, W..In-situ observation of fracture behavior of Sn-3.0Ag-0.5Cu lead-free solder during three-point bending tests in ESEM[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2012:649-655. |
| [16] | 刘继雄;赵爱民;江海涛;唐荻;水恒勇.钛钢复合板弯曲过程的扫描电镜原位观察[J].北京科技大学学报,2012(4):424-429. |
| [17] | 王豫;马玉明.钢和铸铁的热浸铝研究[J].华东冶金学院学报,1990(03):38-47. |
| [18] | 胡增智 .铁铝金属间化合物组织和性能的研究[D].哈尔滨工业大学,2010. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%