Question B.3 This question concerns powder metallurgy. The hollow tube shown in Figure B3 is to be manufactured from sintered stainless steel powder. a) The final component (shown in Figure B3) will have a relative density of 90 %. Given that stainless steel has a theoretical density of 7.85 g/cm³, what is the component mass? [5 marks] b) Before sintering, the green part has a length of 157.5 mm. Assuming uniform shrinkage, what relative density is the green part? State any other assumptions you make. [7 marks] c) What issues may occur if you were to compress the loose powder into a green part using a standard uniaxial press? What kind of compression would you suggest to avoid these problems and how to avoid these issues? [6 marks] d) Three different powder batches are considered for use in the process. Each consists of perfectly spherical particles with the following sizes: Batch 1: uniform diameter of 50 μm, i.e. all powder particles are the same size. ⚫ Batch 2: uniform diameter of 200 μm, i.e. all powder particles are the same size. ⚫ Batch 3: diameters normally distributed from 50 μm to 200 μm. Discuss whether there will be any difference in the relative density of the different powder batches if they are poured into separate identical moulds and how this may affect the sintering process. 30.00 40.00 150.00 Figure B3: Final desired component geometry, all dimensions in mm [7 marks]