在～102K/s、～103K/s和～104K/s的冷速条件下研究了凝固速度对无铅焊料Sn-3.5Ag合金微观组织和显微硬度的影响.结果表明:由于非平衡凝固条件下动力学过冷的影响,导致了该共晶合金实际凝固过程开始于平衡共晶凝固点以下,合金凝固组织中包含初生β-Sn枝晶,且该初生β-Sn枝晶组织随合金凝固速度的提高而发生细化.另外,维氏硬度测试结果表明,无铅焊料Sn-3.5Ag合金在不同冷速条件下的凝固组织与显微硬度的关系符合经典Hall-Petch关系式,即初生β-Sn枝晶细化能显著提高焊料合金的显微硬度.
参考文献
| [1] | Abtewa M;Selvadurayb G .Lead-free solders in microelectronics[J].Materials Science and Engineering R:Reports,2000,27:95. |
| [2] | Wu C M L;Yu D Q;Law C M T et al.Properties of leadfree solder alloys with rare earth element additions[J].Materials Science and Engineering R:Reports,2004,44:1. |
| [3] | 张曙光,何礼君,张少明,石力开.绿色无铅电子焊料的研究与应用进展[J].材料导报,2004(06):72-75. |
| [4] | J.SHEN;Y.C.LIU;H.X.GAO;C.WEI;Y.Q.YANG .Formation of Bulk Ag_3Sn Intermetallic Compounds in Sn-Ag Lead-Free Solders in Solidification[J].Journal of Electronic Materials,2005(12):1591-1597. |
| [5] | Shen J;Liu Y C;Han Y J et al.Formation of bulk intermetallic compound Ag3Sn in slowly-cooled lead-free Sn-4.0wt% Ag solders[J].JMST,2005,21(06):827. |
| [6] | Henderson DW.;Gosselin T.;Sarkhel A.;Kang SK.;Choi WK.;Shih DY. Goldsmith C.;Puttlitz KJ. .Ag3Sn plate formation in the solidification of near ternary eutectic Sn-Ag-Cu alloys[J].Journal of Materials Research,2002(11):2775-2778. |
| [7] | Flemings M C.Solidification Processing[M].New York:McGraw-Hill,1974:122. |
| [8] | Hall E O .The deformation and ageing of mild steel:Ⅲ discussion of results[J].Proceedings of the Physical Society,1951,64:747. |
| [9] | Petch N J .The cleavage strength of polycrystals[J].J Iron Steel Institute,1953,174:25. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%