91 九色视频丝袜_日韩 无码 二区_色欧美日韩亚洲_亚洲中文精品乱码_国产福利在线观看精品_国产欧美午夜久久_被窝福利视频不卡片_榴莲视频黄版下载_亚洲天堂激情_国产凹凸在线一区二区色老头

Magnesium alloys are widely used because of their advantages:

- low density, one-third lighter than aluminum, and its specific strength (ratio of tensile strength to density) is higher than that of aluminum alloy;

- high fatigue limit;

- can withstand greater impact loads than aluminum alloys;

- good thermal conductivity;

- good castability; good dimensional stability;

- easy to recycle;

- Good machinability;

- have better damping performance;

- It is superior to engineering plastics in many aspects and can replace engineering plastics; it has high corrosion resistance in kerosene, gasoline, mineral oil and alkali.

The disadvantage of magnesium alloy is that it has poor corrosion resistance, even if the corrosion resistance of cast alloy is worse than that of aluminum alloy, special protective solvent needs to be added during melting; special mixed sand is needed to make sand mold. In addition, although magnesium alloy has good impact toughness and fatigue strength, it is sensitive to stress concentration; low yield point and small modulus of elasticity also reduce the use value of magnesium alloy as a structural material.