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目前,国内外发动机排气门（见图1）。广泛使用双金属摩擦焊接结构。国内普遍采用的材质:气门头部为SCr21Mn9Ni4N（21-4N）奥氏体钢,杆部为马氏体钢（如4Cr9Si2、4Cr10Si2Mo等）这种双金属焊接气门可充分发挥两种钢材的 优点,满足发动机全部工况的要求。 双金属摩擦焊接气门的关键是焊接处是 否牢固。即气门在工作中承受拉应力和疲劳应力时,确保不在接头处断裂。 一、摩擦焊接工艺特点 摩擦焊接工艺过程简单示意如图2。当运动件相对固定件高速旋转时,在接触面形成高速摩擦变形层,它将机械功转变成热能。
At present, domestic and foreign engine exhaust valve (see Figure 1). Widely used double metal friction welding structure. The material commonly used in China: the valve head for the austenitic steel SCr21Mn9Ni4N (21-4N), martensitic steel rod (such as 4Cr9Si2, 4Cr10Si2Mo, etc.) This bimetallic welding valve can give full play to the advantages of two kinds of steel, Meet the requirements of all engine operating conditions. Bimetal friction welding valve is the key to the welding firm. That the valve withstand tensile stress and fatigue stress in the work, to ensure that the joint is not broken. First, the characteristics of friction welding process Friction welding process simple schematic shown in Figure 2. When the moving parts are rotated at a high speed with respect to the fixing part, a high-speed friction and deformation layer is formed on the contact surfaces, and the mechanical work turns into thermal energy.