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| Strengthen the shot blasting machine |
The shot blasting to strengthen a process based on tens of meters per second high speed will be numerous metal pill pull the projectile to the workpiece surface.In the ejection process due to the workpiece surface tension and the formation of residual compressive stress, so that the organizational structure of the surface layer to be improved, thus greatly improving the ability of the workpiece fatigue strength and stress corrosion cracking, thereby greatly extending the workpiece in frequent reciprocating load conditionsservice life. Formally strengthen the shot blasting is similar to the clean-up shot blasting, but the mechanism of action and purpose are strictly different from the clean-up shot blasting. |
Material enhanced fatigue strength values
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Material
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Hardness
|
Tensile strength
|
Yield point
|
Expansion rate
|
Fatigue strength
|
Enhance the value
|
|
Strengthening
before
|
Strengthened
|
|
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HRC
|
σ/MPa
|
σ/MPa
|
δ/%
|
MPa
|
MPa
|
%
|
|
Pure iron specimen
|
|
342
|
190
|
38
|
144
|
181
|
25.7
|
|
1Cr18Ni9Ti
|
164HBS
|
|
|
|
308
|
362
|
17.5
|
|
20钢
|
137HBS
|
660
|
380
|
23
|
164
|
210
|
28.0
|
|
45钢
|
20-26
|
879
|
776
|
19.8
|
229
|
283
|
23.6
|
|
20Cr钢
|
58-61
|
|
|
|
263
|
394
|
49.8
|
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40Cr钢
|
52-57
|
1570
|
|
8.2
|
350
|
515
|
47.1
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60Si2Mn
|
42-48
|
1480
|
121
|
10.2
|
358
|
515
|
43.9
|
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T8
|
12-15
|
780
|
316
|
9.4
|
210
|
240
|
14.3
|
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|
Corrosion resistance after stress in the material shot blasting to improve value
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Condition
|
Q275 anti-corrosion stress / MPa
|
45 steel anti-corrosion stress / MPa
|
Shot blasting before
|
Blasting
|
Shot blasting before
|
Blasting
|
In the air
|
221
|
289
|
255
|
297
|
In 3% NaCl aqueous solution of ① The
|
80
|
160
|
100
|
200
|
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① Refers to the quality scores。
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The surface hardness of the material shot blasting to improve value
|
Status
|
Surface hardness HV
|
20 Steel
|
45 Steel
|
40 Steel
|
1Cr18Ni9Ti
|
Shot blasting before
|
175
|
185
|
185
|
230
|
Blasting
|
240
|
260～270
|
255
|
460
|
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