PCB科技 - 影響pcb組件焊接質量和厚度的因素

影響焊接質量和厚度的因素 印刷電路板組件
今天我將分享一個話題, 本主題是影響塗層質量和厚度的因素 印刷電路板組件 焊接. 事實上, 金屬間結合層的質量和厚度 印刷電路板組件 焊接與以下因素有關, 具體內容請參見下文.
1 Alloy composition of solder
這個 alloy composition is a key parameter that determines the melting point of the solder paste and the quality of the solder joint.
從一般潤濕理論出發, 大多數金屬的理想釺焊溫度應為15℃.571 degree Celsius higher than the melting point (liquid line) temperature. 對於錫基合金, 建議溫度約為液相線以上30至40℃.
以錫鉛焊料合金為例, 分析了合金成分是决定熔點和焊點質量的關鍵參數.
(1) The melting point and welding temperature of eutectic alloy are the lowest
The melting point of 63Sn-37Pb eutectic alloy is 183 degree Celsius, 63Sn-37Pb共晶合金的熔點為183℃.
The 印刷電路板 焊接溫度也是最低的, 約210 230攝氏度, 以及組件和 印刷電路板電路板 焊接過程中不會損壞. 任何其他合金比率的液相線都高於共晶溫度. 例如, the liquidus of 40Sn-60Pb (point H) is 232 degree Celsius, SMT貼片的焊接溫度約為260 270℃, 明顯超過部件的耐久極限溫度 印刷電路板印製板.

(2) The eutectic alloy has the densest structure, which is beneficial to improve the strength of solder joints;
The so-called eutectic solder is the transition from solid phase to liquid phase or from liquid phase to solid phase at the same temperature, and the fine crystals of this composition
The granular mixture is called a eutectic alloy. 當溫度達到共晶點時, 焊料全部處於液相, when the temperature drops to the eutectic point
id solder suddenly becomes a solid phase, 囙此，當焊點固化時形成的晶體顆粒最小, 結構最密集, 焊點强度最高. 其他合金的凝固時間較長, 首先結晶的粒子會長大, 這會影響焊點的强度.
(3) The eutectic alloy has no plastic range or viscosity range during the solidification process, which is conducive to the control of the welding process;
As long as the eutectic alloy reaches the eutectic point temperature when the temperature is raised, 它會立即從固相變為液相； 相反地, 只要在冷卻和凝固過程中溫度降至共晶點, 它將立即從液相轉變為固相, 囙此，當合金熔化和凝固時，共晶沒有塑性範圍.
The solidification temperature range (plastic range) of the alloy has a great influence on the welding processability and the quality of the solder joints. Wide plastic range
alloy,
當合金凝固時，形成焊點需要很長時間. If any vibration (including 印刷電路板 deformation) occurs in the 印刷電路板 合金凝固過程中的成分, 它會導致“焊點干擾”, 這可能會導致焊點開裂，並導致設備過早損壞.
根據上述分析, 可以得出結論，合金成分是决定焊膏熔點和熔點質量的關鍵參數.
因此, 無論是傳統錫鉛焊料還是無鉛焊料, 焊料的合金成分要求盡可能低共晶或接近低共晶.
Solder alloy
Second, the degree of oxidation of the alloy surface
The oxide content on the surface of the alloy powder also directly affects the solderability of the solder paste. Because diffusion can only enter clean metal surfaces
OK. 雖然助焊劑具有清除金屬表面氧化物的效果. 但這並不能消除嚴重的氧化問題. 合金粉末的氧含量要求低於0.5%, and it is best to control it below the minus 6th power of 80*10.
總之, 關於影響焊接質量和厚度的因素 印刷電路板組件, 電子編輯將在這裡向您介紹, 我希望能幫助你, 非常感謝。.