Everyone knows how to prevent PCB bending and board warping from going through the reflow furnace. The following is an explanation for everyone:

1. Reduce the influence of temperature on PCB board stress

由於“溫度”是電路板應力的主要來源，只要降低迴流焊爐的溫度或減緩回流焊爐中電路板的升溫和冷卻速度，板彎曲翹曲的發生就會大大增加。減少。 但是，可能會出現其他副作用，例如焊錫短路。

2.使用高Tg片材

Tg是玻璃化轉變溫度，即材料從玻璃態轉變為橡膠態的溫度。 材料的Tg值越低，板子進入回流爐後開始軟化的速度越快，變成軟膠狀態的時間也會變長，板子的變形當然會更嚴重. 使用較高Tg的板材可以增加其承受應力和變形的能力，但材料的價格相對較高。

3.增加電路板的厚度

In order to achieve the purpose of lighter and thinner for many electronic products, the thickness of the board has left 1.0mm, 0.8mm, and even a thickness of 0.6mm. It is really difficult for such a thickness to keep the board from deforming after the reflow furnace. It is recommended that if there is no requirement for lightness and thinness, the board* can use a thickness of 1.6mm, which can greatly reduce the risk of bending and deformation of the board.

4. Reduce the size of the circuit board and reduce the number of puzzles

Since most of the reflow furnaces use chains to drive the circuit board forward, the larger the size of the circuit board will be due to its own weight, dent and deformation in the reflow furnace, so try to put the long side of the circuit board as the edge of the board. On the chain of the reflow furnace, the depression and deformation caused by the weight of the circuit board can be reduced. The reduction in the number of panels is also based on this reason. Low dent deformation.

5. 二手爐盤夾具

If the above methods are difficult to achieve, *reflow carrier/template is used to reduce the amount of deformation. The reason why the reflow carrier/template can reduce the bending of the plate is because it is hoped whether it is thermal expansion or cold contraction. The tray can hold the circuit board and wait until the temperature of the circuit board is lower than the Tg value and start to harden again, and can also maintain the size of the garden.

如果單層托盤不能減少電路板的變形，則必須加蓋板，將電路板與上下托盤夾住。 這樣可以大大減少通過回流爐的電路板變形問題。 但是，這種烤箱托盤相當昂貴，而且必須手動放置和回收。

6.使用Router代替V-Cut使用子板
由於V-Cut會破壞電路板之間面板的結構強度，盡量不要使用V-Cut子板或減少V-Cut的深度。