PENGUKURAN PENGARUH TEKANAN PERAH PADA TEGANGAN SISA PADUAN AlSi SQUEEZE CASTING DENGAN TEKNIK DIFRAKSI SINAR-X

MEASUREMENT OF PRESSURE DIE EFFECT ON THE RESIDUAL STRESS OF SQUEEZE CASTING AlSi ALLOY USING X-RAY DIFFRACTION TECHNIQUE. The measurement of residual stresses on squeeze casting AlSi alloys has been carried out. The residual stresses were measured in the inter-granular areas around the grain boundaries of the phases by using X-ray diffraction techniques. The tailoring of diffraction method and Rietveld analysis could be applied to calculate the average lattice strains of the phases and the profile parameters (FWHM) in the specimens. The graph shows that the aluminum phase was in compressive-tensile stresses while the silicon phase was in totally compressive stresses. The domination of aluminum composition in the specimens tends to affect the residual stress behaviour of the squeeze casting AlSi alloys. The stress distribution of the alloys follows the profile of stress curve of aluminum phase, even-though the strains were dominated by silicon phase in negative strains. The result shows that the hydrostatic residual stresses curve of squeeze casting AlSi alloys fluctuates between approximately -800GPa and 400 GPa.