问题:莱氏体有高温莱氏体和低温莱氏体之分,区分温度为727℃。...
Thursday, October 17, 2024
Tuesday, February 11, 2025
问题:根据含S、P杂质元素的多少,碳素钢可分为()和()...
Friday, August 22, 2025
问题:柴油的腐蚀性由()、()、()及()四个指标来控制。...
Sunday, May 19, 2024
问题:观察分析汽车上的车架、半轴套管、法兰、车身总成、车门、侧围等都是...
Thursday, September 15, 2022
问题:为什么球墨铸铁的强度和韧性要比灰口铸铁、可锻铸铁高?...
Tuesday, December 5, 2023
Saturday, August 9, 2025
Monday, September 12, 2022
问题:石油常压蒸馏所得到的不同成分的馏分温度范围是:汽油()℃;煤油(...
Thursday, September 15, 2022
Sunday, September 11, 2022
问题:采用冷冲压方法制造汽车油底壳应选用()A、45钢B、T10A钢C、08钢...
Friday, December 29, 2023
Friday, August 22, 2025
Thursday, July 3, 2025
Tuesday, May 28, 2024
Sunday, August 10, 2025
问题:低碳钢与中碳钢常用正火代替退火,改善其组织结构和切削加工性。...
Thursday, July 3, 2025
Thursday, September 15, 2022
问题:轮胎、密封条、胶管、胶带减震元件及耐油元件是由哪种橡胶制成的?...
Saturday, March 22, 2025
Wednesday, July 5, 2023
Sunday, May 19, 2024