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Die casting technology is machine, mould and alloy three essential factors, Will pressure, velocity and time unification process.
1, pressure：
Is casting obtain organization density and contour clear important factors, 2, shot force: is injection institutions in pushing injection of force, press the piston moves thousand new calculation: 1, more than 10 ates tonnage than pressure: is melting metal in synthesis pressure indoor unit area by pressure, is by the shot force and pressure chamber cross-sectional area ratio of the relationship, the result of the formula: P ratio = P shoot/F room P than - than pressure (gpa pressure effect and influence of specific pressure increases, crystallization: fine, Thin crystal layer thickening, filling, features and improving, the surface quality improvement, ease but significant effect on tensile strength improved, elongation decreased。
To fill the condition the influence: in high pressure under the action of filling mold, lifting high temperature alloy castings, liquidity improvement, be helpful for quality improvement。
2, the factors affecting stress：
1), high melting point, efficient than the pressure, 2), high temperature liquid alloy, mold temperature too low, pressure loss increases, 3), casting gating system design, structure and large in the resistance, stress, the lower the efficiency, 4), pressure regulating shot force, points pressurization system, can improve injection characteristics, improve the quality of castings；
3, ejection process variations in pressure：
1), low-pressure shoot (usually less than 0.3 meters per second), 2), high-speed injection (1-5 meters seconds), 3), build pressure 0.05-0.03 seconds, 4 than pressure selection:
1), according to the required strength die-casting choice than pressure, general casting choose 480 kilograms. Force/cm2, high density of castings choose 940 kilograms. Force/cm2, 2), according to the wall thickness consider: casting thin section iron castings - ingate thin, resistance is big, filling than pressure big, Thick wall casting - ingate thick, small resistance, filling, when than the small, Complex shape castings - ingate speed, the machine fits the mold force, mould strength to consider.
3), bilge type force and clamping force; Points bilge type force is also called backpressure, each side direction says lateral force, 5, bilge type injection speed：
1), usually in the punch speed and ingate speed two kinds, 2), injection speed slow punch promote liquid metal to ingate 0.3 meters/SEC. 3), rapid ingate fill cavity 4-9 meters per second, quick injection effect, improve injection speed, function into heat energy, good fluidity, help to eliminate flow mark, cold-lap defects, increase mechanical properties and Jane surface quality, injection rate option choose and consideration:
1), provide heat conduction and specific heat sex, the temperature range of solidification。
2), mold temperature low speed can be low, and vice speed can be high。
3），Complex casting adopts high voltage shoot speed. Ingate speed 15-70 meters per second, (liquid metal）
4、The punch ejection velocity and ingate speed relations：
The punch press Mr Shoot higher speed, the liquid metal tramsotal speed is more high。
5、Option to choose speed：
1），Straight runnet 15-25 meters per second, 2), horizontal runnet 20-35 m/s, inside watering KouBeiZaiDao 30 wide 70 meters per second, thin castings with no choice of 3 millimeter Rong ingate speed 38-46 meters per second, thick casting 5 mm chooses ingate speed 46-40 meters per second, thicker casting 5 millimeter above choose ingate speed 47-27 millimeter seconds, regulator whole methods: regulator whole injection punch speed, replace pressure chamber diameter, change ingate cross-sectional area, 6, pressure. Speed was measured and analyzed:
1), die-casting parameters tester, first and second line and vasopressor normal moveout time, 2), pressure starting point for die-casting quality influence:
When primary starting filling 80%, in secondary and pressurization starting time, finally hold normal moveout pressure, otherwise it will affect the quality.
3), injection punch head wear suffocate suffocate, injection impeded the effects of parameters for die-casting, 4), injection room and punch wear the analysis of the reason：
Injection room with the punch cooperation degree clearance less than 0.1 millimeter, punch and pressure chamber produces high temperature vulnerability, back and forth friction pressure chamber diameter greaten, punch decrescent, will have the punch aluminum soap gets stuck, impact pressure chamber transmission speed and pressure and refuses to force, to so punch to use high-temperature lubricant, injection lever will open cooling water, also want to choose the punch materials, general selection ductile iron or beryllium bronze, etc.
