Camera based process monitoring of the CO2 and Nd:YAG laser welding process: Experiences from applications in the automotive industry

The Nd:YAG laser welding process of AZ31B alloys was performed by using the six-axis robot in this work. The microstructure characterization of AZ31B auto-welded joints was studied by using scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). The laser welding process resulted in the formation of equiaxed grains in the center of the fusion zone (FZ) and columnar grains near the FZ boundary, meanwhile some eutectic β-Mg17Al12 particles were observed in the microstructure. No clear heat affected zone (HAZ) was observed in the welded AZ31B joint. Furthermore, some pores were observed in the base material (BM) and FZ.

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Optimization of Nd:YAG-Laser Welding Process for Inconel 718 Alloy

Materials Science Forum - Progress in Light Metals, Aerospace Materials and Superconductors ◽

10.4028/0-87849-432-4.1305 ◽

2007 ◽

pp. 1305-1308

Author(s):

Min Xiao ◽

C. Poon ◽

Priti Wanjara ◽

Mohammad Jahazi ◽

Z. Fawaz ◽

...

Keyword(s):

Laser Welding ◽

Nd:Yag Laser ◽

Inconel 718 ◽

Welding Process ◽

Inconel 718 Alloy ◽

Laser Welding Process

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Optimization of Nd:YAG-Laser Welding Process for Inconel 718 Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.546-549.1305 ◽

2007 ◽

Vol 546-549 ◽

pp. 1305-1308 ◽

Cited By ~ 2

Author(s):

Min Xiao ◽

Cheung Poon ◽

Priti Wanjara ◽

Mohammad Jahazi ◽

Zouheir Fawaz ◽

...

Keyword(s):

Laser Welding ◽

Nd:Yag Laser ◽

Continuous Wave ◽

Electron Beam Welding ◽

Laser System ◽

Welding Process ◽

Aircraft Engine ◽

Inconel 718 Alloy ◽

Engine Components ◽

Laser Welding Process

Ni-based superalloys are extensively used in the manufacture of aircraft engine components because of their excellent heat-resistant and corrosion-resistant properties. The principal joining processes for Ni-based superalloys are TIG welding, MIG welding, submerged arc welding, electron beam welding, and CO2 laser welding. In this investigation, a robotic 4-kW continuous-wave Nd:YAG laser system was used to identify the optimal laser welding process for 2.0 mm thick Inconel (IN) 718 sheets. The effect of various processing parameters, which included power input, welding speed, weld geometry and filler wire, was studied using the Taguchi design of experiment (DOE) methodology. The DOE methodology enabled the evaluation of the relationship between the process parameters and the quality of the welded joints, from which the optimal Nd:YAG laser welding process was developed for IN718 alloy. Joint quality was examined by tensile and nondestructive testing methods. Using the optimal process established in this research, mechanically-sound welds with narrow fusion and heat-affected zones were produced. The outcome of this research demonstrates the feasibility of the application of Nd:YAG laser in the joining of IN718 sheets for the manufacture of aircraft engine components.

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LASER WELDING PROCESS MONITORING SYSTEMS: ADVANCED SIGNAL ANALYSIS FOR QUALITY ASSURANCE

Series in Optics and Photonics - An Introduction to Optoelectronic Sensors ◽

10.1142/9789812834133_0022 ◽

2009 ◽

pp. 494-514

Author(s):

Giuseppe D'Angelo

Keyword(s):

Quality Assurance ◽

Laser Welding ◽

Process Monitoring ◽

Signal Analysis ◽

Welding Process ◽

Monitoring Systems ◽

Laser Welding Process

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Laser Welding Characteristics of Cold Rolled Carbon Steel Utilize Continuous Wave Nd:YAG Laser

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.345-346.1461 ◽

2007 ◽

Vol 345-346 ◽

pp. 1461-1464 ◽

Cited By ~ 1

Author(s):

Byung Heon Shin ◽

Young Tae Yoo ◽

Ho Jun Shin ◽

Ji Hwan Kim

Keyword(s):

Carbon Steel ◽

Laser Welding ◽

Nd:Yag Laser ◽

Laser Power ◽

Continuous Wave ◽

Welding Process ◽

High Energy ◽

Optimum Conditions ◽

Cold Rolled ◽

Laser Welding Process

Laser welding process is widely used in the industrial area due to its less affects to base metal than general welding. Laser welding has characteristics that highly affect ratio, deeply penetration depth and small heat affected zone(HAZ) due to its in a short time melting and then solidification by a high energy absorption rate. The objective of this research work is to investigate the optimum conditions of a cold rolled carbon steel(SCP1) in a laser welding process using a Nd:YAG laser with a continuous wave(CW). The determination of optimum conditions were performed to change the laser power, beam speed, focus length and then carry out an butt welding. From the results of the investigation, it has been shown that the optimal welding condition without defects in the vicinity of the welded area and with a good welding quality is 1325W of the laser power, 1.4m/min of laser welding speed and 0mm of focus position.

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Microstructural and Mechanical Characterization of a TRIP-800 Steel Welded By Laser-CO2 Process

MRS Proceedings ◽

10.1557/proc-1276-10 ◽

2010 ◽

Vol 1276 ◽

Author(s):

G. Y. Perez-Medina ◽

P. Zambrano ◽

H. F. López ◽

F. A. Reyes-Valdés ◽

V. H. López-Cortés

Keyword(s):

Laser Welding ◽

Automotive Industry ◽

Annealing Temperature ◽

Process Condition ◽

Welding Process ◽

Controlled Cooling ◽

The Impact ◽

Holding Temperature ◽

Laser Welding Process

AbstractThis paper presents results on the impact of Laser CO2 process variables on the weldability, phase transformations and tensile properties of a TRIP800 Steel. The microstructure of this steel is comprised of ferrite, bainite and retained austenite phases. This is obtained by controlled cooling from the intercritical annealing temperature to the isothermal bainitic holding temperature. These steels have been increasingly used in the last 10 years in the automotive industry and for these materials to be used effectively; the influence of material and the CO2 laser welding process condition must be clearly understood. Hence, in this work the effect of the welding process on the resultant microstructures and on the exhibited mechanical properties is investigated. It is found that the tensile strength of welded specimens falls below 800 MPa and that the elongation becomes 15 % or lower. In turn, this clearly indicates that the implemented laser welding process leads to a reduction in the TRIP800 steel toughness.

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