一、前 言 在空气机械制造中,使用材料的强度必须能耐使用条件下产生的应力,同时作为选择材料的要点,还应考虑下面几个问题。 1.气体种类及成分:主要是气体腐蚀及夹杂物引起的磨损问题,必须对予想到的损伤具有充分的抵抗性; 2.使用温度:要求耐高温强度及抗高温腐蚀性。在低温下,必须考虑材料的脆化; I. INTRODUCTION In the air machinery manufacturing, the strength of materials used must be able to withstand the stress generated under the conditions of use, as well as the main points of the selection of materials, but also consider the following questions. 1. Gas types and composition: Mainly gas corrosion and inclusions caused by wear and tear, must be presumed to have sufficient resistance to damage; 2. Operating temperature: the requirements of high temperature strength and high temperature corrosion resistance. At low temperatures, the embrittlement of the material must be considered;