Question

Please select one of casting methods which you think is the most suitable for the following object and give a description why you make this selection

1. Titanium hip joint                                    
2. Engine block of a motor car                                                  
3. a scale model toy car                                                       
4. Large steel sheet                                      
5. Pipes/tubing

     

Answer 1

a. Titanium hip joint: Investment casting is the best casting method for this purpose. The desired surface roughness can easily be obtained by this casting method. The bi-lamellar microstructure can be obtained from this casting by simple heat treatment. Also, this method helps to increase the HCF strength.

b.Engine block of a motor car: Sand casting and Die casting are two primary casting methods used for the engine block of a motor car. Die casting is an economical choice from a cost-effective perspective as the die wear out easily because of the high temperature of molten metal. It also gives the desired surface roughness.

c. Scale model toy car: Resin casting is most suitable for this purpose because this gives a fine and smooth texture and paint hardly falls off from this surface. Resin can have better shape, offer tight shut lines. No zinc pest used.

d. Large steel sheet: Formed by continuous casting and roll forming by preheated to a high temperature.

e. pipes/tubes: For the materials like pipes and tubes or long hollow materials extrusion molding is used. In extrusion molding plastic resin is directly inserted into the mold. A force is applied to the cross-section of the mold and mold is forced to pass through the die. Required Shape of the material is determined or controlled by the die not by the shape of the mold. Mold is melted by the heat supplied to the extrusion machine. After the extrusion, plastic is resolidified by some cooling medium or air. Only thermoplastic is used for the extrusion.