Friction Welding 摩擦焊

Friction welding is a solid state welding process. Solid state welding are those welding process in which no external heat is applied or no molten or plastic state involves. In this type of welding, welding occurs due to external pressure applied into the solid state. In friction welding process, both the plates or work piece to be joint are in either rotating or moving relative to one another. This relative movement produces friction which displaces material plastically on contact surface. A high pressure forced applied till completed the weld. This welding is used to joint steel bars, tubes up to 100 mm diameter.
摩擦焊接是固态焊接工艺。固态焊接是指不使用外部热量或不涉及熔融或塑性状态的焊接工艺。在这种类型的焊接中,焊接是由于施加在固态中的外部压力引起的。在摩擦焊接过程中,待连接的板或工件都相对于彼此旋转或移动。这种相对运动产生摩擦,使材料在接触面上发生塑性位移。施加高压直至完成焊接。这种焊接用于连接直径达100 mm的钢筋和钢管。

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1 Principle 原理

Friction welding works on basic principle of friction. In this welding process, the friction is used to generate heat at the interference surface. This heat is further used to join two work pieces by applying external pressure at the surface of work piece. In this welding process, the friction is applied until the plastic forming temperature is achieved. It is normally 900-1300 degree centigrade for steel. After this heating phase, a uniformly increasing pressure force applied until the both metal work pieces makes a permanent joint. This joint is created due to thermo mechanical treatment at the contact surface.

摩擦焊接的基本原理是摩擦。在这个焊接工艺中,摩擦被用来在干涉表面产生热量。该热量进一步用于通过在工件表面施加外部压力来连接两个工件。在这个焊接工艺中,施加摩擦直到达到塑性成形温度。钢的温度通常为900-1300摄氏度。在这个加热阶段之后,施加一个均匀增加的压力,直到两个金属工件形成永久连接。该连接是由于接触表面的热机械处理而形成的。

2 Working 工作

There are many types of friction welding processes which works differently. But all different these processes involves common a working principle which can be summarize as follow.
摩擦焊接工艺有很多种,其工作原理各不相同。但所有这些不同的工艺都涉及一个共同的工作原理,可以总结如下:

  • First both the work pieces are prepared for smooth Round surface. One of them is mounted on a rotor driven chuck and other one remains stationary.
    首先,准备好两个光滑的圆形表面工件,其中一个安装在转子驱动的卡盘上,另一个保持固定。
  • The rotor allows rotating at high speed thus it makes rotate mounted work piece. A little pressure force is applied on the stationary work piece which permits cleaning the surface by burnishing action.
    转子允许高速旋转,从而使安装的工件旋转。在固定工件上施加一点压力,就可以通过抛光来清洁表面。
  • Now a high pressure force applied to the stationary work piece which forces it toward rotating work piece and generates a high friction force. This friction generates heat at the contact surface. It is applied until the plastic forming temperature is achieved.
    现在,施加到固定工件上的高压力将其推向旋转的工件并产生高摩擦力。这种摩擦在接触表面产生热量,一直施加到达到塑性成型温度为止。
  • When the temperature is reached the desire limit, the rotor is stopped and the pressure force is applied increasingly until the whole weld is formed.
    当达到所需温度极限时,转子停止运转,压力逐渐施加,直到形成整个焊缝。
  • This welding is used to weld those metals and alloys which cannot be welded by other method.
    该焊接用于焊接其他方法无法焊接的金属和合金。

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3 Types 类型

3.1 Continuous induce friction welding 连续感应摩擦焊

This welding is same as we discussed above. In this welding process, the rotor is connected with a band brake. When the friction crosses the limit of plastic temperature, the band brake comes into action which stops the rotor but the pressure applied on the work piece increasingly until the weld is formed.
这种焊接与我们上面讨论的相同。在该焊接过程中,转子与带式制动器连接。当摩擦力超过塑料温度极限时,带制动器开始起作用,这会停止转子,但施加在工件上的压力会逐渐增加,直到形成焊接为止。
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3.2 Inertia friction welding 惯性摩擦焊

In this type of friction welding the band brake is replaced by the engine flywheel and shaft flywheel. These flywheels connect chuck to the motor. In the starting of the welding, both flywheels are connected with one another. When the speed or friction reaches its limit, the engine flywheel separated from the shaft flywheel. Shaft flywheel has low moment of inertia which stops without brake. The pressure force is continuously applied to the work piece until the weld is formed.
在这种摩擦焊接中,带式制动器由发动机飞轮和轴飞轮代替。这些飞轮将卡盘连接到电动机。在焊接开始时,两个飞轮相互连接。当速度或摩擦力达到极限时,发动机飞轮与轴飞轮分离。轴飞轮的惯性矩小,无需制动即可停止。压力不断施加到工件上,直到形成焊缝。
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4 Application 应用

  • For welding tubes and shafts.
    用于管和轴的焊接
  • It is mostly used in aerospace, automobile, marine and oil industries.
    它主要用于航空航天,汽车,船舶和石油工业
  • Gears, axle tube, valves, drive line etc. components are friction welded.
    齿轮,轴管,阀门,传动线等部件均采用摩擦焊接工艺
  • It is used to replace forging or casting assembly.
    用于替代锻件或铸造件
  • Hydraulic piston rod, truck rollers bushes etc. are join by friction welding.
    液压活塞杆,卡车滚轮衬套等通过摩擦焊接连接
  • Used in electrical industries for welding copper and aluminum equipment’s.
    用于电气工业中的铜铝设备的焊接
  • Used in pump for welding pump shaft (stainless steel to carbon steels).
    用于焊接泵轴的泵(不锈钢到碳钢)。
  • Gear levers, drill bits, connecting rod etc. are welded by friction welding.
    变速杆,钻头,连杆等通过摩擦焊焊接。

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5 Advantages and Disadvantages 优点与缺点

5.1 Advantages 优点

  • It is environment friendly process without generation smoke etc.
    这是一种环保的工艺,不会产生烟雾等
  • Narrow heat affected zone so no change in properties of heat sensitive material.
    狭窄的热影响区,因此不改变热敏材料的性能
  • No filler metal required.
    不需要填充金属
  • Welding strength is strong in most cases.
    在大多数情况下,焊接强度很强
  • Easily automated.
    易于自动化
  • High welding speed.
    焊接速度快
  • High efficiency of weld.
    焊接效率高
  • Wide variety of metal can be weld by this process.
    通过这种方法可以焊接各种各样的金属

5.2 Disadvantages 缺点

  • This is mostly used only for round bars of same cross section.
    这通常只用于相同截面的圆钢
  • Non-forgeable material cannot be weld.
    不可伪造材料不能焊接
  • Preparation of work piece is more critical
    工件的准备更为关键
  • High setup cost.
    安装成本高
  • Joint design is limited.
    连接设计有限