问题
问答题 简答题
型壁移动的含义?对铸件的影响?
答案
参考答案:
金属液浇入铸型后砂型壁发生位移的现象称为型壁移动。它对铸件的尺寸精度,缩孔,缩松等缺陷的形成有很大的影响。造成型壁移动的原因有:在金属液的热作用下型壁发生膨胀,砂型紧实率低,在金属压力作用下,砂型进一步被紧实.
型壁移动的含义?对铸件的影响?
参考答案:
金属液浇入铸型后砂型壁发生位移的现象称为型壁移动。它对铸件的尺寸精度,缩孔,缩松等缺陷的形成有很大的影响。造成型壁移动的原因有:在金属液的热作用下型壁发生膨胀,砂型紧实率低,在金属压力作用下,砂型进一步被紧实.
从所给的选项中选择最佳项完成对话。 | |
Jim: I'm staying in bed. I had a bad cold. John: I'm sorry to hear that. 2_____ Jim: Yes. My mother took me to the hospital. What's the matter? John: I got two tickets to Titanic this evening. 3_____ Jim: Yes, I'd like to. John: 4_____ Jim: Let's meet at half past six. John: 5_____ Jim: Let's meet at the school gate. John: OK. See you then. Jim: See you. |