Dissimilar Alloy Sheets Research Articles

Experimental Investigation on Mechanical and Distortion Characteristics of Titanium/Aluminium Dissimilar Metal Joint Using Laser Beam Welding

Laser beam welding (LBW) is based on interaction between the laser source and base metals. Different methods have been developed recently to produce weld joints of light metals. This produces good weld bead to simplify the structure and reduce the weight and cost to meet the important concerns of aerospace industry. To achieve these, Ti (Ti6Al4V) and Al (AA2024) dissimilar alloy sheets are welded with butt joint configuration using Nd: YAG pulsed laser welding unit. The weldment is subjected to tests to evaluate mechanical and distortion characteristics. From the test results, it is found that LBW is very much suitable for joining Titanium/Aluminium (Ti/Al) alloy sheets.

Experimental investigation of friction stir blind riveting process for similar and dissimilar alloy sheets

Friction stir blind riveting (FSBR) is a new joining method which eliminates the need to predrill a hole for rivet insertion. A new one-sided mechanical joining process, friction stir blind riveting (FSBR) was developed to form lap-shear joints for similar and dissimilar alloy sheets in different combinations. The similar and dissimilar joints are made from copper, Al 5052-H32, Al 6061-T6 metals. The process window was investigated of CNC machines using only three spindle speeds: 1110, 1750 and 2750 rpm. FSBR joints were observed and discussed during tensile testing. All the similar and dissimilar joints are well fabricated at 1750 rpm. Tensile testing results show that any material with copper combinations (copper used as a top plate) at 1750 rpm as riveting speed gives the appreciable ultimate tensile strength. Further study revealed micro structure of the joint interfaces, when compared with different combinations.

Mechanical Clinching of Titanium and Aluminum-Lithium Sheet Materials

This paper deals with the join-ability of extensible die mechanical clinching in titanium and aluminium-lithium sheet materials. Latest developments in extensible die mechanical clinching processes for sheet materials are reviewed. Clinching process tests were carried out for the dissimilar alloy sheets combinations. To increase the join-ability, TA1 sheets were heated to 700 °C by an oxyacetylene flame gun. The temperature was controlled by an infrared thermometer. Tensile-shear tests were carried out to characterize the mechanical properties of the clinched joints. The quality assessment and failure mode of clinched joints were studied. Results showed that clinched joints of titanium and aluminium-lithium have very good join-ability and load-bearing capacity. It can be inferred from the energy absorption analyse results that the clinch joints failed with neck fracture mode can absorb more energy than that of the clinch joints failed with button separation mode.