PENGUKURAN PENGARUH TEKANAN PERAH PADA TEGANGAN SISA PADUAN AlSi SQUEEZE CASTING DENGAN TEKNIK DIFRAKSI SINAR-X[Measurements of Pressure Die Effects on The Residual Stresses of Squeeze Casting AlSi Alloys using X-Ray Diffraction Techniques]

Abstract

The measurements 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 aluminium phase was in compressive-tensile stresses while the silicon phase was in totally compressive stresses. The domination of aluminium 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 aluminium 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 approxiamately -800GPa and 400 GPa.