影響拋(噴)丸強度的主要因素有：
(1)拋丸大小：拋丸越大，沖擊動能越大，拋丸強度也越大，但拋丸的覆蓋率降低。因此，在保證拋丸強度的同時，應(yīng)盡量選用較小的拋丸。此外，噴丸尺寸還受零件形狀限制。當(dāng)零件上有溝槽時，拋丸直徑應(yīng)小于溝槽內(nèi)圓半徑的一半。拋丸粒度常在6—50目之間選用。
(2)拋丸的硬度：當(dāng)拋丸硬度比零件硬度高時，它的硬度值的變化不影響拋丸強度；當(dāng)拋丸比零件軟時，若拋丸硬度值降低，拋丸強度也降低。
(3)拋丸速度：拋丸速度增加時，拋丸強度也增加，但速度過高時，拋丸破損量增加。
(4)噴射角度：拋丸射流與待噴表面垂直時，拋丸強度高，因此一般都應(yīng)保持在這種狀態(tài)下進行拋丸處理。若受零件的形狀限制，必須用小角度噴丸時，應(yīng)適當(dāng)加大噴丸尺寸與速度。
(5)拋丸的破碎量 ：拋丸破片的動能低，破碎了的拋丸越多，噴丸強度降低，而且不規(guī)則的碎丸會劃傷零件表面，因此應(yīng)經(jīng)常清除碎丸，保證噴丸完整率大于85%。拋丸設(shè)備基本相同，只需采用一些輔助裝置來更嚴格的控制拋丸過程。
中譯英：
Effect of toss(spray)pill strength are the main factors:
(1) size: the larger shot blasting, shot blasting impact kinetic energy is big, but also higher strength, but the coverage rate reduce blasting. Therefore, in ensuring blasting strength while, should try to use smaller shot. In addition, shot size is also affected by the shape of parts limited. When the parts on which a groove, shot blasting diameter should be less than half of the trench within a circle of radius. Shot size in 6-50 between the head selection.
(2) when the shot blasting hardness hardness than the hardness of parts is high, its hardness change does not affect the impact strength; when the shot than parts of soft, if shot hardness value decreased, shot blasting strength also decreases.
(3) shot blasting velocity speed increases, shot blasting strength also increased, but the speed is too high, shot blasting damage increase.
(4) shot blasting jet and spray angle perpendicular to the surface to be sprayed, shot blasting intensity is highest, which generally should be maintained in this state for shot blasting. If the restrictions on the shape of parts, must use the small angle of shot peening, should be appropriately increased the size and speed of shot peening.
(5) a shot blasting crushing amount: shot blasting fragments of the kinetic energy is low, broken shot more, shot peening strength is reduced, and irregular broken pill will scratch the surface, therefore should always clear crushed pill, ensure the integrity rate of greater than 85% shot peening. Shot blasting equipment is basically the same, only need to use assistive devices to more strictly controlled blasting process.
(圖/文http://www.alingl.cn/)
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