Nov_Dec_AMP_Digital

iTSSe TSS A D V A N C E D M A T E R I A L S & P R O C E S S E S | N O V E M B E R / D E C E M B E R 2 0 2 0 4 9 iTSSe TSS RESIDUAL STRESS BUILDUP IN Ti COMPONENTS PRODUCED BY COLD SPRAY ADDITIVE MANUFACTURING (CSAM) V. Luzin, O. Kirstein, S.H. Zahiri, and D. Fraser Cold spray has been developed recently to be used as an additive manufacturing technology in order to fabricate bulk components. Residual stresses are known to build up in coatings made by cold spray. Therefore, cold spray additive manufacturing (CSAM) is also expected to generate residual stress in bulk parts and components, and that residual stress can lead to shape distortions or component cracking. The re- sidual stress analysis has been applied to some generic sample shapes, a thick patch deposit and a vertical wall, produced by CSAM out of Ti powder. The residual stress mapping has been achieved using neutron diffraction technique and analyzed- within a modeling approach. (Fig. 1) T he Journal of Thermal Spray Technology (JTST), the official journal of the ASM Thermal Spray Soci- ety, publishes contributionson all aspects—fundamental and practical—of thermal spray science, including processes, feedstock manufacture, test- ing, and characterization. As the primary vehicle for ther- mal spray information transfer, its mission is to synergize the rapidly advancing thermal spray industry and related industries by presenting research and de- velopment efforts leading to advancements in implementable engineering applications of the technology. The August issue is a special issue on Advanced Residual Stress in Thermal Spray and Cold Spray Coatings. The first four articles highlighted below are from this special issue. The fifth article is from the October issue. In addition to the print publication, JTST is avail- able online through springerlink.com . For more information, visit asminternational.org/tss. COMPARISION OF RESIDUAL STRESS MEASUREMENTS CONDUCTED BY X-RAY STRESS ANALYSIS AND INCREMENTAL HOLE DRILLING METHOD K. Bobzin, W. Wietheger, M.A. Knoch, A. Schacht, U. Reisgen, R. Sharma, and L. Oster The level of residual stresses is of great importance for many applications. In this work, the two established residual stress analysis methods, x-ray stress analysis and incremen- tal hole-drilling combined with electronic speckle pattern in- terferometry, are compared. Each stress analysis method has its specific limitations. Furthermore, the residual stress state of a material is influenced by its processing history. To com- pare both methods, aluminum-based specimens (AlCu6Mn, AlZn5.5MgCu) with different processing histories were inves- tigated. Measurements with both methods were conducted on the same specimens and on the same measurement spots. (Fig. 2) JTST HIGHLIGHTS 13 Fig. 1 — Experimental maps of three stress components measured in the bar sample central cross section. Fig. 2 — XRD graph of measurement point P3 of B1 (top) and C2 (bottom) at φ=308.6°.