因瓦合金因具有低的膨胀系数而用于制作显示器荫罩。为在200℃成形条件下建立合理的加工工艺,有必要研究它的高温响应。在加热炉内对试样进行拉伸试验,并用应变计测量。结果表明,对于790～850℃退火试样,变形抗力随加热温度从室温升至180℃而明显下降,此后在180～220℃时屈服强度与抗拉强度分别稳定在120～130MPa和300～320MPa内,且在试验条件下提高退火或加热温度,延伸率增大,但弹性模量基本不变化。

Invar alloy is employed as the material of the shadow mask of a color picture or display tube because of its low coefficient of expansion being beneficial to the gain of high clarity.In order to provide the experimental basis for the formation of Invar alloy shadow mask at 200℃, its responses at elevated temperature were observed in the conditions of the static load and uniaxial tension by means of strain gage.The results show that for various annealing treatments at 790~850℃, the stresses is evidently dropped with increasing the heating temperature from about 20 to 180℃, and thereafter is fluctuated in 120~130MPa for the yielding strength and in 300~320MPa for the ultimate strength.The specific elongation is increased with the rise of annealing and heating temperatures, but the elastic modulus is nearly unchanged.