合金元素影響加熱時奧氏體形成的速度和奧氏體晶粒的大小。
The rate of Austenite Formation during heating and the size of austenite grain.
(1)對奧氏體形成速度的影響: Cr、Mo、W、V等強碳化物形成元素與碳的親合力大, 形成難溶于奧氏體的合金碳化物, 顯著減慢奧氏體形成速度;Co、Ni等部分非碳化物形成元素, 因增大碳的擴散速度, 使奧氏體的形成速度加快;Al、Si、Mn等合金元素對奧氏體形成速度影響不大。
(1) the formation rate of influence on Cr, Mo, W: austenitic and V strong carbide forming elements and carbon affinity, carbides formed insoluble in austenite, the formation rate was reduced Co and Ni austenite; some non carbide forming elements, because the diffusion rate of carbon increases, the formation of austenite speed; Al, Si, Mn and other alloy elements had little effect on the formation rate of austenite.
(2)對奧氏體晶粒大小的影響:大多數合金元素都有阻止奧氏體晶粒長大的作用, 但影響程度不同。強烈阻礙晶粒長大的元素有:V、Ti、Nb、Zr等;中等阻礙晶粒長大的元素有:W、Mn、Cr等;對晶粒長大影響不大的元素有:Si、Ni、Cu等;促進晶粒長大的元素:Mn、P等。
(2) the effect of austenite grain size: most of the alloying elements have the effect of preventing the growth of austenite grain, but the influence degree is different. Strongly hinder the grain growth of the elements are: V, Ti, Nb, Zr; secondary hinder the grain growth of the elements are: W, Mn and Cr had little effect on grain growth; elements are: Si, Ni, Cu etc.; promote the grain growth of elements: Mn, P etc..
2. 合金元素對過冷奧氏體分解轉變的影響
Effect of 2 alloying elements on the decomposition and transformation of over Cooling Austenite
除Co外, 幾乎所有合金元素都增大過冷奧氏體的穩定性, 推遲珠光體類型組織的轉變, 使C曲線右移, 即提高鋼的淬透性。常用提高淬透性的元素有:Mo、Mn、Cr、Ni、Si、B等。必須指出, 加入的合金元素, 只有完全溶于奧氏體時, 才能提高淬透性。如果未完全溶解, 則碳化物會成為珠光體的核心, 反而降低鋼的淬透性。另外, 兩種或多種合金元素的同時加入(如, 鉻錳鋼、鉻鎳鋼等), 比單個元素對淬透性的影響要強得多。
In addition to Co, almost all alloy elements will increase the stability of supercooled austenite pearlite transformation, delayed type of organization, make the C curve to the right, to improve the hardenability of steel. Commonly used to improve the quenching of the elements are: Mn, Cr, Mo, Ni, Si, B, etc.. It must be pointed out that the addition of alloying elements, only completely dissolved in the austenite, can improve the quenching performance. If not completely dissolved, the carbide will become the core of the pearlite, but reduce the steel. In addition, adding two or more alloying elements at the same time (e.g., chromium manganese steel, chrome nickel steel etc.), better than single element influence on the hardenability.