bga器件无铅再流焊温度场仿真研究.rar
bga器件无铅再流焊温度场仿真研究,bga器件无铅再流焊温度场仿真研究页数：59字数：28859摘要尽管焊接缺陷、焊点可靠性等焊接质量仍然与焊膏印刷、 贴片等前面多道工序有关，但据研究结果和生产统计表明，更多的焊接缺陷来源于再流焊工艺本身。再流焊是预先在pcb(printed circuit board)板的焊接部位(焊盘)放置适量和适当形式的焊料，然后...
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BGA器件无铅再流焊温度场仿真研究
页数：59 字数：28859
摘 要
尽管焊接缺陷、焊点可靠性等焊接质量仍然与焊膏印刷、 贴片等前面多道工序有关，但据研究结果和生产统计表明，更多的焊接缺陷来源于再流焊工艺本身。再流焊是预先在PCB(Printed Circuit Board)板的焊接部位(焊盘)放置适量和适当形式的焊料，然后贴放表面组装元器件，经固化(在采用焊膏时)后，再利用外部热源使焊料再次流动达到焊接目的的一种成组或逐点焊接工艺。只要设置合适的再流焊设备的各区温度，几乎能完全满足各类表面组装元器件对焊接的要求，实现可靠的连接。但目前在国内还没有建立再流焊接温度场的模型，仍采用反复试验的方法制定再流焊接工艺，造成了巨大的财力和人力的浪费。因此，对再流焊温度场的仿真研究极其重要。
本文研究的是BGA器件无铅再流焊过程中的温度场仿真。用ANSYS软件，根据所用无铅钎料的性能，分析了获得良好焊点性能的再流焊温度曲线；利用传热学的理论，将再流焊中红外加热转化为对流加热，结合再流焊设备对PCAs(Printed Circuit Assemblis)加热的实际物理过程，建立了红外热风再流焊方法的传热数学模型；根据再流焊设备的尺寸，结合获得良好性能产品的再流焊焊膏熔化温度曲线的要求，根据BGA的封装，建立仿真所用的PCAs有限元模型；获得再流焊炉各区的加载温度：进一步对PCAs的再流焊接温度场进行了动态模拟，获得了PCAs整体组件的动态温度场和比较满意的再流焊工艺仿真。
通过对两种加载曲线的仿真结果的比较，获得适合无铅加载的曲线设置以及曲线的优化方法
关键词： 无铅；再流焊；仿真；温度场；表面组装；建模
Abstract
Although the welding defects, welding quality solder joint reliability is still with the solder paste printing, placement, etc. in front of the multi-channel processes, but according to research results and production statistics show that more of welding flaws from the reflow process itself. Reflow soldering is a solder that connect SMD or SMC with PCB by melting the solder utilize external heat sonrce make solder reflow and solidify the solder by cooling it (while adopting the soldering paste)．Reliable connection of various components is attainable when the temperature section of flow oven is setup suitably．The traditional approach of experimentally analysing production defects would be costly and virtually impossible for the temperature field model is not built homeland inside．An alternative to this approach is to derive computational and numerical models to simulate the reflow soldering process．
This study is lead-free BGA devices during reflow temperature field simulation. With ANSYS software, according to the performance of lead-free solder analysis analysis for good performance of the reflow solder temperature curve ;whit the heat transfer theory, we will go in the infrared reflow into a convection heating, combined with the reflow equipment of the PCAs (Printed Circuit Assemblis) the actual physical process of heating, the establishment of an infrared hot air reflow method of heat transfer model; according to the size of the reflow equipment, combined with performance products for good solder paste reflow melting temperature curve requirements, according to BGA packages, the establishment of simulation by the finite element model used in PCAs; access various parts of the reflow furnace load temperature: further PCAs re-flow soldering temperature field in the dynamic simulation, the dynamic component of the overall temperature of PCAs field and more satisfied with the reflow process simulation. By comparison of two kinds of load curves’ simulation results. The study can obtain the curve for lead-free settings, and load optimization curve.
Key words: Lead-free; Refolw soldering ;Simulation; temperature field; SMT; Modeling
目 录
1 绪论 1
1.1无铅软钎焊研究的背景 1
1.1.1 无铅钎料的种类 1
1．2 PCB组件概述 3
1.2.1PCB的结构 3
1.2.2PCB的分类 4
1.3 BGA的概述 5
1.4 再流焊接建模与仿真的意义 6
1．5 研究发展现状 6
1.5.1国外研究发展现状 6
1.5.2国内研究发展现状 9
1．6 本课题研究的内容 10
2 再流焊设备及工艺要求 10
2.1再流焊热源 10
2.1.1再流焊热源类型与主要特点 10
2.1.2 红外加热风再流焊原理 11
2.1.3 红外线辐射加热风再流焊设备 12
2.2无铅钎料的选择及其特性 14
2.2.1选择背景 14
2.2.2选择的原则 15
2.3再流焊温度曲线 16
2.3.1无铅再流焊接温度关键参数的确定 17
2.3.2无铅再流焊温度曲线参数的设定 17
2.3.3无铅再流焊接温度曲线的管理 19
2.4 本章小结 20
3 再流焊数学模型的建立 20
3.1基本理论 20
3.2热传递的基本方式 21
3.3边界条件 22
3.4再流焊温度场的数学模型 23
3.5小结 26
4 PCAs的温度场仿真 27
4.1 定义材料类型和材料属性 27
4.1.1所需材料清单 27
4.1.2 Cu箔的热参数 27
4.1.3 FR-４的热特性 28
4.1.4无铅焊料的热特性 29
4.1.5 BGA的热参数 29
4.2 ANSYS软件介绍 30
4.2.1ANSYS软件分析方法 30
4.2.1关于ANSYS的热分析 31
4.3 创建有限元几何模型 32
4.4 边界条件 35
4.5 加载和求解 36
4.5.1加载过程 36
4.5.2求解过程 37
4.5.3求解的结果及分析 39
4.5.4 加载曲线的选取及优化 47
4.6 本章小结 48
5 结论 49
谢辞 51
参考文献 52
页数：59 字数：28859
摘 要
尽管焊接缺陷、焊点可靠性等焊接质量仍然与焊膏印刷、 贴片等前面多道工序有关，但据研究结果和生产统计表明，更多的焊接缺陷来源于再流焊工艺本身。再流焊是预先在PCB(Printed Circuit Board)板的焊接部位(焊盘)放置适量和适当形式的焊料，然后贴放表面组装元器件，经固化(在采用焊膏时)后，再利用外部热源使焊料再次流动达到焊接目的的一种成组或逐点焊接工艺。只要设置合适的再流焊设备的各区温度，几乎能完全满足各类表面组装元器件对焊接的要求，实现可靠的连接。但目前在国内还没有建立再流焊接温度场的模型，仍采用反复试验的方法制定再流焊接工艺，造成了巨大的财力和人力的浪费。因此，对再流焊温度场的仿真研究极其重要。
本文研究的是BGA器件无铅再流焊过程中的温度场仿真。用ANSYS软件，根据所用无铅钎料的性能，分析了获得良好焊点性能的再流焊温度曲线；利用传热学的理论，将再流焊中红外加热转化为对流加热，结合再流焊设备对PCAs(Printed Circuit Assemblis)加热的实际物理过程，建立了红外热风再流焊方法的传热数学模型；根据再流焊设备的尺寸，结合获得良好性能产品的再流焊焊膏熔化温度曲线的要求，根据BGA的封装，建立仿真所用的PCAs有限元模型；获得再流焊炉各区的加载温度：进一步对PCAs的再流焊接温度场进行了动态模拟，获得了PCAs整体组件的动态温度场和比较满意的再流焊工艺仿真。
通过对两种加载曲线的仿真结果的比较，获得适合无铅加载的曲线设置以及曲线的优化方法
关键词： 无铅；再流焊；仿真；温度场；表面组装；建模
Abstract
Although the welding defects, welding quality solder joint reliability is still with the solder paste printing, placement, etc. in front of the multi-channel processes, but according to research results and production statistics show that more of welding flaws from the reflow process itself. Reflow soldering is a solder that connect SMD or SMC with PCB by melting the solder utilize external heat sonrce make solder reflow and solidify the solder by cooling it (while adopting the soldering paste)．Reliable connection of various components is attainable when the temperature section of flow oven is setup suitably．The traditional approach of experimentally analysing production defects would be costly and virtually impossible for the temperature field model is not built homeland inside．An alternative to this approach is to derive computational and numerical models to simulate the reflow soldering process．
This study is lead-free BGA devices during reflow temperature field simulation. With ANSYS software, according to the performance of lead-free solder analysis analysis for good performance of the reflow solder temperature curve ;whit the heat transfer theory, we will go in the infrared reflow into a convection heating, combined with the reflow equipment of the PCAs (Printed Circuit Assemblis) the actual physical process of heating, the establishment of an infrared hot air reflow method of heat transfer model; according to the size of the reflow equipment, combined with performance products for good solder paste reflow melting temperature curve requirements, according to BGA packages, the establishment of simulation by the finite element model used in PCAs; access various parts of the reflow furnace load temperature: further PCAs re-flow soldering temperature field in the dynamic simulation, the dynamic component of the overall temperature of PCAs field and more satisfied with the reflow process simulation. By comparison of two kinds of load curves’ simulation results. The study can obtain the curve for lead-free settings, and load optimization curve.
Key words: Lead-free; Refolw soldering ;Simulation; temperature field; SMT; Modeling
目 录
1 绪论 1
1.1无铅软钎焊研究的背景 1
1.1.1 无铅钎料的种类 1
1．2 PCB组件概述 3
1.2.1PCB的结构 3
1.2.2PCB的分类 4
1.3 BGA的概述 5
1.4 再流焊接建模与仿真的意义 6
1．5 研究发展现状 6
1.5.1国外研究发展现状 6
1.5.2国内研究发展现状 9
1．6 本课题研究的内容 10
2 再流焊设备及工艺要求 10
2.1再流焊热源 10
2.1.1再流焊热源类型与主要特点 10
2.1.2 红外加热风再流焊原理 11
2.1.3 红外线辐射加热风再流焊设备 12
2.2无铅钎料的选择及其特性 14
2.2.1选择背景 14
2.2.2选择的原则 15
2.3再流焊温度曲线 16
2.3.1无铅再流焊接温度关键参数的确定 17
2.3.2无铅再流焊温度曲线参数的设定 17
2.3.3无铅再流焊接温度曲线的管理 19
2.4 本章小结 20
3 再流焊数学模型的建立 20
3.1基本理论 20
3.2热传递的基本方式 21
3.3边界条件 22
3.4再流焊温度场的数学模型 23
3.5小结 26
4 PCAs的温度场仿真 27
4.1 定义材料类型和材料属性 27
4.1.1所需材料清单 27
4.1.2 Cu箔的热参数 27
4.1.3 FR-４的热特性 28
4.1.4无铅焊料的热特性 29
4.1.5 BGA的热参数 29
4.2 ANSYS软件介绍 30
4.2.1ANSYS软件分析方法 30
4.2.1关于ANSYS的热分析 31
4.3 创建有限元几何模型 32
4.4 边界条件 35
4.5 加载和求解 36
4.5.1加载过程 36
4.5.2求解过程 37
4.5.3求解的结果及分析 39
4.5.4 加载曲线的选取及优化 47
4.6 本章小结 48
5 结论 49
谢辞 51
参考文献 52
