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Prediction Models on Distribution of Inherent Strains in T Type Welding Structure

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Journal of Materials Science & Technology 2003年第z1期19卷 202-204页

作者： Peng HE Jicai FENG Jiecai HAN yiyu qian National Key Laboratory of Advanced Welding Production Technology HIT Harbin 150001 China National Key Laboratory of Advanced Welding Production Technology HIT Harbin 150001 China National Key Laboratory of Advanced Welding Production Technology HIT Harbin 150001 China National Key Laboratory of Advanced Welding Production Technology HIT Harbin 150001 China

A fundamental theory for the analysis of residual welding stresses and deformation based on the inherent strain distribution along the welded joint is introduced. The method of predicting maximum hardness Hv(y, z) and maximum inherent strain gmax is given. The model T.E.P-Tav-hardness calculation is proposed to predict distribution of inherent strains in T type welding structure. By T.E.P-Tav-hardness calculation, distribution of longitudinal inherent strains can be predicted in T type welding structure, and calculation and experimental results are consistent.

关键词： Inherent strain, Residual welding stresses, T type welding

Simulation on Thermal Integrity of the Fin/Tube Brazed Joint of Heat Exchangers

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Journal of Materials Science & Technology 2003年第z1期19卷 71-72页

作者： yiyu qian Feng GAO Fengjiang WANG Hui ZHAO State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

In the applications of heat exchangers, the fin efficiency of heat transfer is the key issue. Thermal distribution withinthe brazed joints in heat exchanger under loading conditions is investigated in this paper. Simulated results showedthat the thermal distribution at the brazed joint zone is related to not only the geometry of the fin and tube, butalso the brazed joint topology. A poor brazed joint will result in very poor heat transfer. Thermal contact resistanceis adopted to analyze the fin heat efficiency.

关键词： Thermal integrity, Fin efficiency, Thermal contact resistance, FEM

Microstructure and Strength of the TiB2 Cermet/TiAl Joint Diffusion Bonded with Ni Interlayer

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Journal of Materials Science & Technology 2003年第z1期19卷 181-183页

作者： Zhuoran LI Jicai FENG Jian CAO yiyu qian State Key Lab of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Lab of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Lab of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Lab of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

Vacuum diffusion bonding of TiB2 cermet to TiAl -based alloys using Ni interlayer has been carried out at 1123～1323 K for0.6～3.6 ks under 80 MPa. The effects of joining parameters on the microstructure of the joints and mechanical propertieswas investigated. The results showed that a TiAlNi2 intermetallic layer and two Ti, Al, Ni solid solution layers were formed atthe interface of Ni/TiAl. The shear strength was 110 MPa with bonding temperature at 1223 K, bonding time for 1.8 ks andbonding pressure under 80 MPa.

关键词： Microstructure, Strength, TiB2, TiAl

SPREADING PHENOMENON OF Al/Cu CONTACTING REACTION BRAZING

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Acta Metallurgica Sinica(English Letters) 1989年第10期2卷 266-271页

作者： CHEN Dinghua qian yiyu HUANG Jihua Harbin Institute of Technology,Harbin,China Divison of Welding,Harbin Institute of Technology,Harbin.China

The reactive spread behaviour of Cu particles on the surJace of Al has been *** role of oxide film and the .formation mechanism of the joint during Al/Cu contacting reaction brazing have been discussed.

关键词： Al/Cu interface brazing reaction spread oxide film

纳米压痕法测量Sn-Ag-Cu无铅钎料BGA焊点的力学性能参数

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金属学报 2005年第7期41卷 775-779页

作者：王凤江钱乙余马鑫哈尔滨工业大学现代焊接生产技术国家重点实验室哈尔滨150001 亿铖达工业有限公司深圳518101

对Sn-3.0Ag-0.5Cu无铅体钎料和Sn-4.0Ag-0.5Cu无铅钎料BGA(ball grid array)焊点进行了Berkovich 纳米压痕法实验,通过改变不同的加载速率研究了钎料的蠕变特征.钎料压痕载荷-位移曲线蠕变部分表现出了明显的加载速率相关性.基于Oliver-... 详细信息

对Sn-3.0Ag-0.5Cu无铅体钎料和Sn-4.0Ag-0.5Cu无铅钎料BGA(ball grid array)焊点进行了Berkovich 纳米压痕法实验,通过改变不同的加载速率研究了钎料的蠕变特征.钎料压痕载荷-位移曲线蠕变部分表现出了明显的加载速率相关性.基于Oliver-Pharrr法确定的体钎料和BGA焊点的Young’s模量分别为9.3和20 GPa.基于压痕做功概念确定的体钎料和BGA焊点的应变速率敏感指数分别为0.1111和0.0574.钎料的力学性能有着明显的尺寸效应.

关键词： Sn-Ag-Cu 纳米压痕 Young’s模量应变速率敏感指数

Relative Damage Stress: Dominant Mechanical Factor for the Failure of Soldered Joints under Temperature Cycling

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Journal of Materials Science & Technology 2001年第1期17卷 193-194页

作者： Xin MA yiyu qian and Hongyuan FANG National Key Laboratory of Welding, Harbin institute of TechnologY, Harbin 150001, China F. Yoshida Department of Mechanical Engineering, Hiroshima University, Higashi-Hiroshima 739, Japan Harbin Inst Technol Natl Key Lab Welding Harbin 150001 Peoples R China Hiroshima Univ Dept Mech Engn Higashihiroshima 739 Japan

By temperature normalization of the concept of equivalent damage stress proposed by Lemaitre, a new concept of relative damage stress has been put forward as the dominant mechanical factor for the failure of soldered joints under temperature cycling. Finite element numerical simulation results showed that the highest value of relative damage stress occurred at the high temperature hold time during temperature cycling history.

关键词： Damage Stress damage stress simulation results soldered joints

Factors of effecting creep rupture of SMT solder joints

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China Welding 1994年第1期3卷 15-21页

作者： Zhu Ying Fang Hongyuan and qian yiyu (Harbin Institute of Technology)Cui Dianheng (Fourteenth Institute of the Ministry of Mechanical and Electronic Industry of China)Ding Kejian (Qunli Metal Materials Factory,Wu Xi)

The reliability of SMT soldered joints is one of the most important problems which need to be solved in the application of SMT. In this paper, the influence of grain size, stress and intermetallic compounds in joints is studied by means of testing the creep rupture life of joints at high temperature. It shows that all the crack surface consists of transgranular and intergranular fracture at 125℃, and grain size and stress are different because of different cooling *** the grain size is large and stress in joints is small, the creep rupture life is longer; otherwise, the life of joints decreases because of the viscid flow on grain boundary. When the Cu-Sn intermetallic compounds are present in the joints,the crack usually initiatesat the Cu-Sn compounds, the fracture tended to happen at the compounds area, and the creep rupture life will decrease with the thickness increase of Cu-Sn intermetallic compounds.

关键词： SMT soldering SnPb solder creep rupture

SiC/TiAl扩散连接接头的界面结构及连接强度

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焊接学报 1999年第3期20卷 170-174页

作者：刘会杰冯吉才钱乙余哈尔滨工业大学现代焊接生产技术国家重点实验室

对常压烧结的ＳｉＣ陶瓷与ＴｉＡｌ金属间化合物进行了真空扩散连接。采用扫描电镜、电子探针和Ｘ射线衍射分析等手段确定了反应产物的种类和接头的界面结构，并用拉剪试验评价了接头的连接强度。研究结果表明，ＳｉＣ与... 详细信息

对常压烧结的ＳｉＣ陶瓷与ＴｉＡｌ金属间化合物进行了真空扩散连接。采用扫描电镜、电子探针和Ｘ射线衍射分析等手段确定了反应产物的种类和接头的界面结构，并用拉剪试验评价了接头的连接强度。研究结果表明，ＳｉＣ与ＴｉＡｌ扩散连接中生成了ＴｉＡｌ２、ＴｉＣ和Ｔｉ５Ｓｉ３Ｃｘ三种新相，接头的界面结构为ＳｉＣ／ＴｉＣ／（ＴｉＣ＋Ｔｉ５Ｓｉ３Ｃｘ）／（ＴｉＡｌ２＋ＴｉＡｌ）／ＴｉＡｌ。在１５７３Ｋ和１．８ｋｓ的连接条件下，接头室温剪切强度达到２４０ＭＰａ，高温（９７３Ｋ）剪切强度达到２３０ＭＰａ。

关键词： TiAl 扩散连接界面结构接头强度碳化硅

基于润湿识别的 SMT 激光软钎焊焊点质量控制研究

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机械工程学报 1998年第5期34卷 106-110页

作者：梁旭文王春青姜伟雁钱乙余中国科学院上海冶金研究所传感技术国家重点实验室哈尔滨工业大学

采用高速摄影试验方法研究表面组装激光软钎焊焊点动态形成过程及焊点红外辐射信号与焊点形成过程的关系，发现钎料的润湿过程造成红外辐射信号及其动态微分信号的突变，提出基于润湿识别的焊点质量控制方法及算法。结果表明，该控制算... 详细信息

采用高速摄影试验方法研究表面组装激光软钎焊焊点动态形成过程及焊点红外辐射信号与焊点形成过程的关系，发现钎料的润湿过程造成红外辐射信号及其动态微分信号的突变，提出基于润湿识别的焊点质量控制方法及算法。结果表明，该控制算法能保证形成良好的激光软钎焊焊点并严格避免烧毁。根据信号的特征还可以识别出多种工艺缺陷并可进行预测控制。

关键词：激光软钎焊润湿识别质量控制焊点