Local plastic deformation in cutting zone during turning is affected by technological conditions of the processes. Therefore it is needful to know detail structure changes of plastic deformed material during machining. It is localised, asymmetric deformation which operates at very large strains and exceptionally high strain rates. Three areas of intensive local plastic deformation in cutting zone were observed: the primary area of plastic deformation in shear plane, the secondary area of plastic deformation caused by friction of chip to tool face and the tertiary area of plastic deformation caused by friction of tool to machined surface. Local strain in these three areas was estimated by measurement of deformation of grains on metallographic cut. The effect of grains boundaries self-orientation caused by grains deformation was evaluated using stereology. But the orientation is not the same as deformation and so a correlation between the grain deformation and grain orientation was used. The turning piece was made of CK45 (1.0503) carbon steel. The specimen of cutting zone was obtained by using internal stress method.
Purpose -The purpose of this paper is to study the effect of the addition of a small amount of Al (0.1 percent) on the properties of lead-free solder type Sn-4Ag-0.5Cu (SAC 405). Design/methodology/approach -The soldering properties of wettability and spreadability on a Cu substrate were studied, and the effect of Al on the growth of intermetallic compounds (IMCs) was observed. The shear strength of soldered joints was assessed. For comparison, soldering and strength tests were carried out on SAC 405 and SAC 405 þ Al solders. Soldering was performed with an activated flux type ZnCl 2 -NH 4 Cl, with nonactivated flux (rosin), and without flux in the air. Findings -Experimental results show that Al addition slightly reduces the wettability and spreadability of SAC 405 solder. Also, the shear strength is moderately reduced, dropping by 8 MPa on average. Differential scanning calorimetry (DSC) analysis showed that the melting point of SAC 405 þ 0.1%Al solder was increased to 2218C. Originality/value -The positive effect of a small Al addition is due to the fact that it hinders the growth of IMCs formed on the contact surface with Cu substrate. The width of the transition zone of IMC was reduced by approximately 2 to 3 mm, depending on the soldering temperature.
In this article, the effect of process parameters on the microstructure and mechanical properties of AW5083 aluminum alloy weld joints welded by a disk laser were studied. Butt welds were produced using 5087 (AlMg4.5MnZr) filler wire, with a diameter of 1.2 mm, and were protected from the ambient atmosphere by a mixture of argon and 30 vol.% of helium (Aluline He30). The widest weld joint (4.69 mm) and the highest tensile strength (309 MPa) were observed when a 30 L/min shielding gas flow rate was used. Conversely, the narrowest weld joint (4.15 mm) and the lowest tensile strength (160 MPa) were found when no shielding gas was used. The lowest average microhardness (55.4 HV0.1) was recorded when a 30 L/min shielding gas flow rate was used. The highest average microhardness (63.9 HV0.1) was observed when no shielding gas was used. In addition to the intermetallic compounds, β-Al3Mg2 and γ-Al12Mg17, in the inter-dendritic areas of the fusion zone (FZ), Al49Mg32, which has an irregular shape, was recorded. The application of the filler wire, which contains zirconium, resulted in grain refinement in the fusion zone. The protected weld joint was characterized by a ductile fracture in the base material (BM). A brittle fracture of the unshielded weld joint was caused by the presence of Al2O3 particles. The research results show that we achieved the optimal welding parameters, because no cracks and pores were present in the shielded weld metal (WM).
The work is devoted to the study of shear strength of soldered joints fabricated by use of high-temperature solders of types Bi-11Ag, Au-20Sn, Sn-5Sb, Zn-4Al, Pb-5Sn, and Pb-10Sn. The shear strength was determined on metallic substrates made of Cu, Ni, and Ag. The strength of joints fabricated by use of flux and that of joints fabricated by use of ultrasonic activation without flux was compared. The obtained results have shown that in case of soldering by use of ultrasound (UT), higher shear strength of soldered joints was achieved with most solders. The highest shear strength by use of UT was achieved with an Au-20Sn joint fabricated on copper, namely up to 195 MPa. The lowest average values were achieved with Pb-based solders (Pb-5Sn and Pb-10Sn). The shear strength values of these solders used on Cu substrate varied from 24 to 27 MPa. DSC analysis was performed to determine the melting interval of lead-free solders.Keywords: high-temperature solders, lead-free solders, shear strength, ultrasonic soldering, DSC analysis Praca poświęcona jest badaniu wytrzymałości na ścinanie połączeń lutowanych wytwarzanych przy użyciu wysokotemperaturowych stopów lutowniczych typu Bi-11Ag, Au-20Sn, Sn-5Sb, Zn-4Al, Pb-5Sn i Pb-10Sn, na podłożach wykonanych z Cu, Ni i Ag. Porównano wytrzymałość spoin wytwarzanych przy użyciu topnika i spoin wytwarzanych przy użyciu aktywacji ultradźwiękowej bez topnika. Uzyskane wyniki wykazały, że w przypadku lutowania z wykorzystaniem ultradźwięków (UT), wyższa wytrzymałość na ścinanie połączeń lutowanych została osiągnięta dla większości stopów lutowniczych. Najwyższą wytrzymałość na ścinanie przy użyciu UT (tj. 195 MPa) uzyskano dla Au-20Sn na Cu. Najniższe średnie wartości zostały osiągnięte dla lutów na bazie Pb (Pb-5Sn i Pb-10Sn). Wartości wytrzymałości na ścinanie tych lutów na podłożach Cu waha się od 24 do 27 MPa. Analizę DSC przeprowadzono w celu określenia przedziału temperatur topnienia bezołowiowych stopów lutowniczych.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.