Laser beam welding of titanium nitride coated titanium using pulse-shaping

Lima, Milton Sérgio Fernandes de

doi:10.1590/s1516-14392005000300017

Cited by 16 publications

(8 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The CI is given by [24]: In the present study, the prediction error i.e. the difference between η opt and η obs is 0.00028dB, which is within the CI value of ±0.0609 dB, and hence, justifying the adequacy of the additivity of the model.…”

Section: Verification Test Of Optimal Resultssupporting

confidence: 75%

Multiperformance optimization of tensile strength and heat input of laser transformation hardening of commercially pure titanium using Taguchi methodology and utility concept

Badkar¹,

Pandey²,

Buvanashekaran³

2012

Adv produc engineer manag

View full text Add to dashboard Cite

Abstract:Purpose of this paper: The main objective of this research paper is to investigate and evaluate the optimal values of laser process parameters: laser power, scanning speed, and focused position for the simultaneous minimization and maximization of heat input and tensile strength respectively by Taguchi method and utility concept approach in laser transformation hardening of commercially pure titanium sheet of 1.6mm thickness using continuous wave (CW) Nd:YAG laser beam. Design/methodology/approach: The effect of laser process parameters on the heat input and tensile strength properties of commercially pure titanium and subsequent optimal settings of the parameters have been obtained using Taguchi's parametric design approach and utility concept. The response performance is analyzed based on signal-to-noise ratio and analysis of variance (ANOVA). The optimal levels of the laser process parameters were determined through the Analysis of Means (ANOM). Findings: The optimization results revealed that a combination of higher levels of scanning speed and focused position i.e., increase in defocus along with laser power in the lower level play important role in order to simultaneously minimize the heat input and to maximize the tensile strength (σ). The predicted optimal values of tensile strength and heat input of commercially pure titanium sheet produced by laser transformation hardening process are 464 N/mm 2 and 141.667 Watts, respectively, for the optimized laser process parameters with minimum LP=750 Watts, maximum SS=3000mm/min, and lower value of FP=-30mm (increase in defocus). Research limitations/implications: Research range is limited to investigation of optimization laser hardening process parameters for the simultaneous minimization and maximization of heat input and tensile strength respones.of commercially pure titanium. Hardness test responses are also be optimized in future research work. Practical implications: Laser transformation hardening is an innovative and advanced laser surface modification technique has been employed in aerospace, marine, chemical applications, heat exchangers, cryogenic vessels, components for chemical processing and desalination equipment, condenser tubing, airframe skin, and nonstructural components which introduces the advantageous residual stresses into the surface, improving the mechanical properties like wear, resistance to corrosion, tensile strength, and fatigue strength. Originality/value: Authors made an effort to optimize the laser process parameters in order to minmize the heat input and maximize tensile strength of laser transformation hardening of commercially pure titanium using Taguchi methodology and utility concept.

show abstract

Section: Verification Test Of Optimal Resultssupporting

confidence: 75%

Multiperformance optimization of tensile strength and heat input of laser transformation hardening of commercially pure titanium using Taguchi methodology and utility concept

Badkar¹,

Pandey²,

Buvanashekaran³

2012

Adv produc engineer manag

View full text Add to dashboard Cite

show abstract

“…The results show a homogenous distribution due to the laminar flow and the unchanged physical properties of the liquid titanium in solution with nitrogen. In a comparison of the cross-sectional micrograph in Figure 16 with similar investigations in the literature, [37,38] some differences are shown, especially in the homogeneity.…”

Section: Nitrogen Transport and Comparisonsupporting

confidence: 65%

Marangoni Convection during Free Electron Laser Nitriding of Titanium

Höche

Müller

Rapin³

et al. 2009

Metall Mater Trans B

View full text Add to dashboard Cite

Pure titanium was treated by free electron laser (FEL) radiation in a nitrogen atmosphere. As a result, nitrogen diffusion occurs and a TiN coating was synthesized. Local gradients of interfacial tension due to the local heating lead to a Marangoni convection, which determines the track properties. Because of the experimental inaccessibility of time-dependent occurrences, finite element calculations were performed, to determine the physical processes such as heat transfer, melt flow, and mass transport. In order to calculate the surface deformation of the gasliquid interface, the level set approach was used. The equations were modified and coupled with heat-transfer and diffusion equations. The process was characterized by dimensionless numbers such as the Reynolds, Peclet, and capillary numbers, to obtain more information about the acting forces and the coating development. Moreover, the nitrogen distribution was calculated using the corresponding transport equation. The simulations were compared with crosssectional micrographs of the treated titanium sheets and checked for their validity. Finally, the process presented is discussed and compared with similar laser treatments.

show abstract

“…On the other hand controlling so many parameters increases the complexity of laser processing. Lima (2005) has recently shown that pulse shaping technique can be used to prevent cracking in welded TiN coated titanium alloy through an improvement in the transfer of nitrogen to the volume of the weld. The optimum laser parameters and filler wire diameter are investigated by Li et al (1997) in the welding process.…”

Section: Fig 1 -Shielding Gas Nozzle Setups and Oxidation Effectsmentioning

confidence: 99%

“…When the operation temperature exceeds 130 • C, titanium alloys can be used as replacements for aluminium-based materials to achieve improved mechanical properties at elevated temperatures for applications such as the external shells of turbines, the power units for avionics and the landing gear structural components in Boeings 747 and 757 as mentioned (Lima, 2005). Alternatively, as titanium is exhibit very low corrosion rates in human body fluids as demonstrated (Choubey et al, 2005), other applications that are relevant to the medical industry include prosthetic devices such as artificial heart pumps, pacemaker cases, heart valve parts as well as load bearing bone such as for hip bone replacement.…”

Section: Introductionmentioning

confidence: 99%