In order to study the mechanism of vacuum fluxless soldering on the conditions of laser heating, the method of measuring temperature by the thermocouple is used to analyze the spreading and wetting process of both flu...In order to study the mechanism of vacuum fluxless soldering on the conditions of laser heating, the method of measuring temperature by the thermocouple is used to analyze the spreading and wetting process of both fluxless Sn-Pb solder in the vacuum surroundings and flux Sn-Pb solder on Cu pad. Solder spreading and wetting affected by the soldering thermal process is also discussed according to the thermodynamics principle. Results show that vacuum fluxless soldering demands higher temperature, and the fall of the solder surface tension is the important factor achieving fluxless laser soldering.展开更多
Four process parameters, pad diameter, stencil thickness, ball diameter and stand-off were chosen as four control factors. By using an L25 （5^6 ） orthogonal array the ceramic ball grid array （ CBGA ） solder joints...Four process parameters, pad diameter, stencil thickness, ball diameter and stand-off were chosen as four control factors. By using an L25 （5^6 ） orthogonal array the ceramic ball grid array （ CBGA ） solder joints which have 25 different combinations of process parameters were designed. The numerical models of all the 25 CBGA solder joints were developed using the Sugrace Evolver. Utilizing the sugrace coordinate exported from the 25 CBGA solder joints numerical models, the finite element analysis models were set up and the nonlinear finite element analysis of the CBGA solder joints under thermal cycles were pegrormed by ANSYS. The thermal fatigue life of CBGA solder joint was calculated using Coffin-Manson equation. Based on the calculated thermal fatigue life results, the range analysis and the variance analysis were pegrormed. The results show that the fatigue life of CBGA solder joint is affected by the pad diameter, the stencil thickness, the ball diameter and the stand-off in a descending order, the best combination of process parameters results in the longest fatigue life is 0.07 mm stand-off, 0.125 mm stencil thickness of, 0.85 mm ball diameter and 0. 89 mm pad diameter. With 95% confidence the pad diameter has a significant effect on the reliability of CBGA solder joints whereas the stand-off, the stencil thickness and the ball diameter have little effect on the reliability of CBGA solder joints.展开更多
基于小型化星载射频组件的研制需求,综合利用微组装工艺与表面安装工艺的技术优点,开发了一种一体化焊接工艺,通过陶瓷封装高铅植球、印制电路板/腔体焊接和低空洞真空汽相焊接,完成了对系统级封装(System in Package,SiP)器件、多层射...基于小型化星载射频组件的研制需求,综合利用微组装工艺与表面安装工艺的技术优点,开发了一种一体化焊接工艺,通过陶瓷封装高铅植球、印制电路板/腔体焊接和低空洞真空汽相焊接,完成了对系统级封装(System in Package,SiP)器件、多层射频板、射频绝缘子、金属腔体和双面安装器件的一体化高可靠焊接。产品性能测试、环境试验及工艺鉴定试验表明,该工艺在生产周期、装配效率、一次合格率、性能一致性、长期可靠性等方面具有突出的优势。展开更多
针对某型机车电机转子端环与导条钎焊用含镉钎料BAg40CuZnCdNi因列入限用禁用物质目录,急需替代为无镉钎料的问题,采用无镉钎料BAg55ZnCuSn和钎剂SAXONIA Braze Tec h Paste-Type-FH10与原含镉钎料和钎剂QJ102进行对比验证。运用化学分...针对某型机车电机转子端环与导条钎焊用含镉钎料BAg40CuZnCdNi因列入限用禁用物质目录,急需替代为无镉钎料的问题,采用无镉钎料BAg55ZnCuSn和钎剂SAXONIA Braze Tec h Paste-Type-FH10与原含镉钎料和钎剂QJ102进行对比验证。运用化学分析法对验证用钎料进行化学成分分析,DSC熔化温度测试仪(温升曲线法)进行钎料熔化范围分析,高温润湿炉进行钎剂流铺性和钎料润湿性分析,确定了无镉钎料与钎剂的最优组合。转子工艺模卡验证结果表明,电机转子模卡端环与导条钎焊接头拉伸断裂于导条热影响区,力学性能合格,无镉钎料BAg55ZnCuSn和钎剂SAXONIA Braze Tec h Paste-Type-FH10可以用于该型机车电机转子无镉化替代。展开更多
基金This project is supported by National Natural Science Foundation of China !(59671063)
文摘In order to study the mechanism of vacuum fluxless soldering on the conditions of laser heating, the method of measuring temperature by the thermocouple is used to analyze the spreading and wetting process of both fluxless Sn-Pb solder in the vacuum surroundings and flux Sn-Pb solder on Cu pad. Solder spreading and wetting affected by the soldering thermal process is also discussed according to the thermodynamics principle. Results show that vacuum fluxless soldering demands higher temperature, and the fall of the solder surface tension is the important factor achieving fluxless laser soldering.
基金This work was supported by Science Foundation of Guangxi Zhuang Autonomous Region (Contract No. 02336060).
文摘Four process parameters, pad diameter, stencil thickness, ball diameter and stand-off were chosen as four control factors. By using an L25 （5^6 ） orthogonal array the ceramic ball grid array （ CBGA ） solder joints which have 25 different combinations of process parameters were designed. The numerical models of all the 25 CBGA solder joints were developed using the Sugrace Evolver. Utilizing the sugrace coordinate exported from the 25 CBGA solder joints numerical models, the finite element analysis models were set up and the nonlinear finite element analysis of the CBGA solder joints under thermal cycles were pegrormed by ANSYS. The thermal fatigue life of CBGA solder joint was calculated using Coffin-Manson equation. Based on the calculated thermal fatigue life results, the range analysis and the variance analysis were pegrormed. The results show that the fatigue life of CBGA solder joint is affected by the pad diameter, the stencil thickness, the ball diameter and the stand-off in a descending order, the best combination of process parameters results in the longest fatigue life is 0.07 mm stand-off, 0.125 mm stencil thickness of, 0.85 mm ball diameter and 0. 89 mm pad diameter. With 95% confidence the pad diameter has a significant effect on the reliability of CBGA solder joints whereas the stand-off, the stencil thickness and the ball diameter have little effect on the reliability of CBGA solder joints.
文摘基于小型化星载射频组件的研制需求,综合利用微组装工艺与表面安装工艺的技术优点,开发了一种一体化焊接工艺,通过陶瓷封装高铅植球、印制电路板/腔体焊接和低空洞真空汽相焊接,完成了对系统级封装(System in Package,SiP)器件、多层射频板、射频绝缘子、金属腔体和双面安装器件的一体化高可靠焊接。产品性能测试、环境试验及工艺鉴定试验表明,该工艺在生产周期、装配效率、一次合格率、性能一致性、长期可靠性等方面具有突出的优势。
文摘针对某型机车电机转子端环与导条钎焊用含镉钎料BAg40CuZnCdNi因列入限用禁用物质目录,急需替代为无镉钎料的问题,采用无镉钎料BAg55ZnCuSn和钎剂SAXONIA Braze Tec h Paste-Type-FH10与原含镉钎料和钎剂QJ102进行对比验证。运用化学分析法对验证用钎料进行化学成分分析,DSC熔化温度测试仪(温升曲线法)进行钎料熔化范围分析,高温润湿炉进行钎剂流铺性和钎料润湿性分析,确定了无镉钎料与钎剂的最优组合。转子工艺模卡验证结果表明,电机转子模卡端环与导条钎焊接头拉伸断裂于导条热影响区,力学性能合格,无镉钎料BAg55ZnCuSn和钎剂SAXONIA Braze Tec h Paste-Type-FH10可以用于该型机车电机转子无镉化替代。
