研究了激光熔覆后经600-1000 ℃退火处理的FeCoNiCrAl2Si高熵合金涂层的组织和性能. 结果表明, 激光熔覆过程中的快速凝固条件有利于抑制涂层中金属间化合物的析出, 涂层具有bcc结构, 为有序固溶体, 具有较高的硬度(900 HV0.5), 相结构和硬度的高温稳定性好; 涂层组织为树枝晶,Fe, Cr和Si在枝晶间富集, 而Ni, Co和Al在枝晶中富集. 随退火温度升高, Al和Si的偏析程度加剧, 而其余元素的偏析变化不明显. EBSD研究显示熔覆态涂层的枝晶和枝晶间界面分布有大量小角度晶界, 经600 ℃退火5 h后小角度晶界转变为大角度晶界, 晶粒被细化.
The influences of laser rapid solidification and annealing treatment at 600—1000 ℃ on the microstructure and properties of laser clad FeCoNiCrAl2Si high–entropy alloy coating were investigated. The experimental results indicate that the precipitation of intermetallic compounds in the coating could be effectively inhibited by laser cladding with rapid solidification. The coating had simple ordered bcc solid solution phases with high microhardness (900 HV0.5), good high temperature phase stability and softening resistance. The coating was mainly composed of dendrites, Fe, Cr and Si are enriched in interdendritic region, Ni, Co and Al are enriched in dendritic region. As the annealing temperature increase, the segregations of Al and Si increase, but segregations of Fe, Cr, Ni and Co changed little. Massive low angle grain boundaries were distributed at the interface between dendritic and interdendritic microstructures. After annealing at 600 ℃ for 5 hours, the microstructure was greatly refined, and the grain boundary misorientation converted from low to high angles.
[1] Yeh J W, Chen S K, Lin S J, Gan J Y, Chin T S, Shun T T, Tsau C H, Chang S Y. Adv Eng Mater, 2004; 6: 299
[2] Zhang K B, Fu Z Y, Zhang J Y, Shi J, Wang W M, Wang H, Wang Y C, Zhang Q J. J Alloys Compd, 2010; 502: 295
[3] Chou H P, Chang Y S, Chen S K, Yeh J W. Mater Sci Eng, 2009; B163: 184
[4] Hsu C Y, Sheu T S, Yeh J W, Chen S K. Wear, 2010; 268: 653
[5] Wen L H, Kou H C, Li J S, Chang H, Xue X Y, Zhou L. Intermetallics, 2009; 17: 266
[6] Chang H W, Huang P K, Yeh J W, Davison A, Tsau C H, Yang C C. Surf Coat Technol, 2008; 202: 3360
[7] Yao C Z, Zhang P, Liu M, Li G R, Ye J Q, Liu P, Tong Y X. Electrochim Acta, 2008; 53: 8359
[8] Singh S, Wanderka N, Murty B S, Glatzel U, Banhart J. Acta Mater, 2011; 59: 182
[9] Zhang H, He Y Z, Yuan X M, Pan Y. Appl Surf Sci, 2010; 256: 5837
[10] Li M X, He Y Z, Sun G X. Appl Surf Sci, 2004; 230: 201
[11] Zhang S H, Li M X, Cho T Y, Jae H Y, Chan G L, He Y Z. Opt Laser Technol, 2008; 40: 716
[12] Yue T M, Su Y P, Yang H O. Mater Lett, 2007; 61: 209
[13] Shun T T, Hung C H, Lee C F. J Alloys Compd, 2010; 493: 105
[14] Zhang K B, Fu Z F, Zhang J Y, Shi J, Wang W M, Wang H, Wang Y C, Zhang Q C. J Alloys Compd, 2009; 485: L31
[15] Lin C M, Tsai H L, Bor H Y. Intermetallics, 2010; 18: 1244
[16] Tong C J, Chen M R, Yeh J W, Lin S J, Chen S K, Shun T T, Chang S Y. Metall Mater Trans, 2005; 36A: 1263
[17] Zhang H, Pan Y, He Y Z. Mater Des, 2011; 32: 1910
[18] Zhang K B, Fu Z Y, Zhang J Y, Wang W M, Lee S W, Niihara K. J Alloys Compd, 2010; 495: 33
[19] Zhu J M, Fu H M, Zhang H F, Wang A M, Li H, Hu Z Q. Mater Sci Eng, 2010; A527: 7210
[20] Zhu J M, Fu H M, Zhang H F, Wang A M, Li H, Hu Z Q. J Alloys Compd, 2011; 509: 3476
