Technology and Properties of Peripheral Laser-Welded Micro-Joints

Abstract

This article presents the results of research on the technology and peripheral properties of laser-welded micro-couplings. The aim of this research was to determine the characteristics of properly made joints and to indicate the range of optimal parameters of the welding process. Thin-walled AISI 316L steel pipes with diameters of 1.5 and 2 mm used in medical equipment were tested. The micro-welding process was carried out on a SISMA LM-D210 Nd:YAG laser. The research methods used were macroscopic and microscopic analyses of the samples, and assessment of the distribution of elements in the weld, the distribution of microhardness and the tear strength of the joint. As a result of the tests, the following welding parameters are recommended: a pulse energy of 2.05 J, pulse duration of 4 ms and frequency of 2 Hz, beam focusing to a diameter of 0.4 mm and a rotation speed of 0.157 rad/s. In addition, the tests show good joint properties with a strength of more than 75% of the thinner pipe, uniform distribution of alloying elements and a complex dendritic structure characteristic of pulse welding.

Development of Laser Welding and Surface Treatment of Metals

“…This Special Issue, entitled “Development of Laser Welding and Surface Treatment of Metals”, is a complementary and valuable resource of knowledge in the following fields: Study of technological conditions of laser welding, investigation of test joints properties [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ]; Analytical and numerical models of heat sources of laser beam and arc welding processes [ 19 , 20 , 22 , 23 ]; Study of laser cladding and investigations of the coating’s properties and tribological characteristics [ 27 , 28 , 29 , 30 , 31 , 32 , 33 ]; Study and development of fusion welding processes, investigation of properties of the deposit produced under forced cooling or underwater conditions [ 34 , 35 , 36 ]; Study of cladding, surfacing, and thermal spraying processes of wear-resistant coatings, characterization of the coatings [ 37 , 38 , 39 ]; Study of application of local strengthening of the thin-walled structure by laser treatment [ 40 ]. …”

“…Study of technological conditions of laser welding, investigation of test joints properties [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ];…”

“…Another study on laser welding was presented by Tofil et al [ 26 ]. They conducted a test of laser welding of thin-walled AISI 316 L steel pipes, with diameters of 1.5 and 2.0 mm, used in medical equipment.…”

Ideas and Assumptions of a New Kind Helical Metal Expansion Joints

“…Currently, laser techniques are widely used, e.g. for cutting [2], welding [3], industrial coatings applications [4], creating textures on the material's surface [5], additive manufacturing [6], etc. Instead the laser forming method uses the phenomenon of distortion in the material as a result of the element's local temperature change.…”

Mechanically assisted laser forming hybrid method in metal expansion joints manufacturing

“…The laser technologies are commonly used nowadays in wide range of manufacturing processes. [2][3][4][5][6]. There will be presented a concept to manufacture MEJ with the hybrid mechanically assisted laser forming method (HMALFM) [7].…”