若因溫度和變形程度選擇不當(dāng)而得到粗大晶粒時，可利用熱處理相變細(xì)化晶粒組織，但對于熱處理中不發(fā)生相變的鋼種，如奧氏體鋼，就必須在鍛造過程中獲得細(xì)小而均勻的晶粒組織，因此對這樣的材料在鍛造時須加倍注意。

If the temperature and degree of deformation and improper selection of coarse grains, the grain refinement phase change heat treatment, but for the steel phase transition does not occur in the heat treatment, such as austenitic steel, it must be in the forging process have fine and uniform grains, so this kind of material in the forging must pay more attention to.

由于熱變形形成纖維組織，會使金屬的力學(xué)性能出現(xiàn)異向性，即縱向力學(xué)性能指標(biāo)中的A，Z，Ak比橫向相應(yīng)的指標(biāo)大得多，兩個方向上的強(qiáng)度Rm。Re差別不大。

Due to the formation of fibrous microstructure by thermal deformation, the mechanical properties of metals will be different. That is, A, Z and Ak in longitudinal mechanical properties are much larger than those itransverse direction, and the strength in two directi is Rm. Re is not very different.

自由鍛造的設(shè)備分為鍛錘和液壓機(jī)兩大類。生產(chǎn)中使用的鍛錘有空氣錘和蒸汽-空氣錘，有些廠還使用結(jié)構(gòu)簡單，投資少的彈簧錘、夾板錘、杠桿錘和鋼絲錘等。

The equipment of free forging can be divided into two categories: forging hammer and hydraulic press. The forging hammers used in production are air hammer and steam-air hammer. Some factories also use spring hammer, splint hammer, lever hammer and steel wire hammer with simple structure and low investment.