【判断题】塑性越好的材料,其伸长率和断面收缩率越小。( )
【多选题】塑性是指材料在外力作用下发生塑性变形而不被破坏的能力。也就是说,材料 持续 发生塑性变形的量越大,塑性就越 (好,差)。而发生塑性变形所需的外力大小与塑性的好与差无关。容易发生塑性变形的材料,其塑性未必就好,反之亦然。反映塑性好坏的指标有两个,即断后 和截面收缩率,前者的代号为δ,后者的代号为ψ,它们都是没有单位的量。
【单选题】动态电路的初始储能为零,仅由外加激励引起的响应称为( )
【简答题】Getting the Writer's Purpose There are a number of ways that a writer can use to convey the purpose of writing and the writer's attitude. These include: How the text layout uses headings, subheadings,...
【判断题】材料的伸长率、断面收缩率数值越小,表明其塑性越好。()
【简答题】从B栏中选出A 栏的答语。 A ( ) 1. May I go shopping? ( ) 2. If you work hard in school, you may go with us. ( ) 3. When do you leave for America? ( ) 4. How far is it from China to Canada? ( ...
【单选题】If you work with a strong will,you will overcome any difficulty___great it is.
【单选题】材料的伸长率、断面收缩率数值越小,表明其塑性越好。()
【单选题】The wonderful work you have finished in the country will . [ ]