聚甲醛塑料,俗称赛钢,为结晶性热可塑性塑料,具明显熔点165~175℃,性质Zui接近金属。
优点 1、具高机械强度和刚性
2、Zui高的疲劳强度
3、环境抵抗性、耐有机溶剂性佳
4、耐反覆冲击性强
5、广泛的使用温度范围(-40℃~120℃)
6、良好的电气性质
7、复原性良好
8、具自已润滑性、耐磨性良好
9、尺寸安定性优
缺点 1、加工过程若长时间高温下易起热分解
2、无自熄性
3、抗酸性差
4、成形收缩率大
用途 电子电器:洗衣机、果汁机零件、定时器组件
汽 车: 车把零件、电动窗零件
工业零件:机械零件、齿轮、把手、玩具、螺杆
Julian - why did you tell all that to the woman?' asked Anne.'You don't usually say so much whenwe are in the middle ofsomething queer!'
'My dear, unsuspecting Anne - do you mean to say that you thoughtthat woman was really what shepretended to be - a woman from anearby farm?' said Julian.
'Well - wasn't she?' said Anne surprised. 'She looked like one - nomake-up - and that old shawl -and she knew all about the oldcottage!'
'Anne - farm-women don't have gold fillings in their teeth,' saidJulian. 'Didn't you notice them whenshe smiled?'