The following article describes results of investigations on influence of laser welding parameters on the weld shape, quality and mechanical properties of 2.0 mm thick butt joints of titanium alloy Ti6Al4V (Grade 5 according to ASTM B265) welded with a new generation disk laser TRUMPF TRUDISK 3302, emitting at 1030 nm, with maximum output power 3300 W at circular laser beam spot, characterized by laser beam divergence 8.0 mm•mrad. The test butt joints of Ti6Al4V titanium alloy sheets were prepared as single square groove (I-type joint) and one-side laser welded without an additional material, at a flat position, using a specially designed system for shielding gas (purity 99.999%). The investigations at the initial stage were focused on detailed analysis of influence of the basic laser welding parameters such as laser power and welding speed on the shape and quality of single bead produced during bead-on-plate welding. Then the optimal parameters were chosen for laser welding of 2.0 mm thick butt joints of the titanium alloy Ti6Al4V. Edges of the titanium alloy sheets were melted in argon atmosphere by the laser beam focused on the top surface of butt joints. The test welded joints were investigated by visual inspection, metallographic examinations, hardness and micro-hardness measurements and mechanical tests such as tensile tests and bending tests. It was found that the welding mode is a keyhole welding and providing high quality of joints requires a special techniques and conditions of laser welding, as well as special gas shielding nozzles is required.
The following article describes results of investigations on influence of laser welding parameters on the weld shape, quality and mechanical properties of 2.5 mm thick butt joints of thermo-mechanically rolled, high yield strength steel for cold forming S420MC (according to EN 10149 - 3 and 060XLK according to ASTM) welded with high power diode laser HPDL ROFIN SINAR DL 020 with rectangular laser beam spot and 2.2 kW output power, and 808 nm wavelength. The investigations at the initial stage were focused on detailed analysis of influence of the basic laser welding parameters such as laser power and welding speed on the shape and quality of single bead produced during bead-on-plate welding. Then the optimal parameters were chosen for laser welding of 2.5 mm thick butt joints of the thermo-mechanically rolled, high yield strength steel sheets for cold forming S420MC. The test joints were prepared as single square groove and one-side laser welded without an additional material, at a flat position. Edges of steel sheets were melted in argon atmosphere by the laser beam focused on the top joint surface. The test welded joints were investigated by visual inspection, metallographic examinations, mechanical tests such as tensile tests and bending tests. It was found that the high power diode laser may be applied successfully for one-side welding of the S420MC steel butt joints. Additionally it was found that in the optimal range of laser welding parameters the high quality joint were produced.
Trials of wlding an alloy based on an Ni3Al phase matrix with a diode laser have been made. In the base metal of Ni3Al, typical casting structures have been found. The Heat Affected Zone consists of a fine-grained structure, whereas in the weld structure, columnar crystals have been observed. A possibility of joining intermetallic phase-based alloys by measn of a diode laser has been affirmed.
The Surface Laser Alloying (SLA) process using High Power Diode Laser (HPDL) with rectangular beam spot and uniform energy distribution across the spot was investigated. The surface of substrate tool steel was alloyed with cobalt based powder injected directly to the weld pool. The parameters investigated were laser power, traveling speed and powder feeding rate. The results showed that it's possible to produce high quality surface layer alloyed with diode laser. Thickness of the alloyed layer is in a range from 0.7 up to 2.5 mm, and its micro hardness exceeds 1000 HV0.2.
KEYWORDS: Laser welding, Semiconductor lasers, High power diode lasers, Metals, Cameras, High power lasers, Temperature metrology, Liquids, Imaging systems, Laser applications
In this paper, results of investigations on the shape of weld pool during High Power Diode Laser (HPDL) welding are presented. The results of tests showed that the shape of weld pool and mechanism of laser welding with a rectangular pattern of 808 nm laser radiation differs distinctly from previous laser welding mechanisms. For all power densities the conduction mode welds were observed and weld pool geometry depends significantly on the welding parameters.
KEYWORDS: Titanium, Semiconductor lasers, Nitrogen, High power diode lasers, Argon ion lasers, Fusion energy, Surface finishing, Laser applications, Argon, High power lasers
In this paper, results of investigations concerning the influence of high power diode laser surface modification of titanium alloy TO4 on structure and properties of the top layer are presented. The results showed that it's possible to produce high quality top layer of 0.15 to 0.7 mm thick. The hardness of the top layer is up to 3100 HV0.2, and the hardness of substrate material is under 200 HV0.2.
Trials of welding an alloy based on an intermetallic Fe-Al phase matrix with a diode laser have been made. Metallographic research has revealed typical structures, characteristic of welding joints. A possibility of laser joining of Fe-Al alloys has been found.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.