TIG Repair Technology For Non-dynamic Load Surface Damage Of Mechanical Supercharger

Cast aluminum alloy has a wide range of applications in the automotive industry.When aluminum alloy castings are damaged during manufacturing or installation,they can be restored to service performance through appropriate repair processes to achieve green manufacturing.The welding repair research object of this paper is the mechanical supercharger with non-dynamic load surface damage(material is ZL101A).The manual Tungsten Inert Gas welding repair technology has the characteristics of small heat input,controllability and low cost.It has great advantages in the repair of the non-dynamic load surface of the supercharger.This paper mainly completed the following works:(1)Research on repair process optimization.Firstly,through pre-experiment,the reasonable process parameters of ZL101 A welding repair were determined,and the influence of each welding parameter on the forming and size of the repairing area was investigated.Then the effects of cleaning time,cleaning current and welding current on the tensile strength of the repaired specimens were studied by orthogonal experiment.The effects of various parameters on tensile strength were found: welding current>cleaning time>cleaning current;the combination of optimal parameters is:welding current 100 A,cleaning time 45 ms,cleaning current 45 A.(2)Optimize the detection of parameter repair effects.The mechanical repair of the non-dynamic load surface of the supercharger was carried out by using the optimal combination of process parameters,and a number of tests were carried out in the repair area.The metallographic photographs of the repaired area show that there are few holes and inclusions in each area,and the metallurgical effect of the cladding material and the base material matrix is better.The microhardness test found that the base material area>cladding area>heat affected zone,the overall hardness curve showed “w” shape.From the tensile test at room temperature,it is found that the fracture is a typical dimple fracture morphology,and the tensile crack initiation position is mostly in the heat affected zone,and the optimal performance is 155 MPa.The relative difference between the thermal expansion coefficient of the shell welding material and the shell material in the range of 70~100 °C of the supercharger is only 5.12%,and the color difference is Lab0.49,which belongs to the category of tiny chromatic aberration.Reach the repair requirements.(3)The life cycle analysis method is used to compare the pollution indexes under the two conditions of manufacturing and repairing the new supercharger housing,and thedischarge of environmental pollution in the manufacturing process is analyzed.