Investigations on the Microstructure and the Fracture Surface of Pulsed Nd: YAG Laser Welding of AISI 304 Stainless Steel

The paper presents pulsed Nd:YAG laser welding of the 304 stainless steels. The welding tests were carried out with various operational parameters. The effects of laser welding variables on the geometry, microstructure and solidification of the weld are considered. The austenitic or ferritic solidification is produced in the 304 austenitic stainless steel depended upon the cooling rate and its chemical compositions. The possiblity of austenitic solidification compared with the ferritic solidification decreases with the chromium to nickel equivalent ratio and that increases with cooling rates. Moreover, more δ ferrite is obtained if the cooling rate is increased or the higher power laser is used. The surface of fracture samples was considered and the reason for failure was investigated. The study shows that the fracture is in ductile type.

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Investigation on Mechanical Properties of Pulsed Nd:YAG Laser Welding on AISI 304 Stainless Steel to AISI 1008 Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.117-119.402 ◽

2011 ◽

Vol 117-119 ◽

pp. 402-408

Author(s):

Shazarel Shamsudin ◽

Phoon Chee Yoon

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Stainless Steel ◽

Laser Welding ◽

High Energy ◽

High Energy Density ◽

304 Stainless Steel ◽

Aisi 304 Stainless Steel ◽

Aisi 304 ◽

Pulsed Nd:Yag Laser Welding

Product with low cost, lightweight and enhanced mechanical properties were the main reasons welding dissimilar materials thrived by most of the industries. The laser welding technique which has high-energy density beam was found suitable of carrying this task. This paper attempts to investigate welding of AISI 304 stainless steel to AISI 1008 steel through Nd:YAG pulse laser method. The main objective of this study was to find out the weldability of these materials and investigate the mechanical properties of the welded butt joints. Peak power, pulse duration and weld speed combinations were carefully selected with the aims of producing weld with a good tensile strength, minimum heat affected zone (HAZ) and acceptable welding profile. Response surface methodology (RSM) approach was adopted as statistical design technique for tensile strength optimization. Statistical based mathematical model was developed to describe effects of each process parameters on the weld tensile strength and for response prediction within the parameter ranges. The microstructure of the weld and heat affected zones were observed via optical microscope. The results indicate the developed model can predict the response within ±9% of error from the actual values.

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Kinetic Model to Investigate the Effect of Cooling Rate on δ-Ferrite Behavior and Its Application in Continuous Casting of AISI 304 Stainless Steel

Metals and Materials International ◽

10.1007/s12540-021-01118-z ◽

2021 ◽

Author(s):

Tahereh Zargar ◽

Fazlollah Sadeghi ◽

Jong Wan Kim ◽

Jae Sang Lee ◽

Yoon-Uk Heo ◽

...

Keyword(s):

Stainless Steel ◽

Kinetic Model ◽

Continuous Casting ◽

Cooling Rate ◽

304 Stainless Steel ◽

Aisi 304 Stainless Steel ◽

Aisi 304 ◽

Δ Ferrite

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Transient Thermal Analysis of CO2 Laser Welding of AISI 304 Stainless Steel Thin Plates

Lecture Notes on Multidisciplinary Industrial Engineering - Manufacturing Engineering ◽

10.1007/978-981-13-6287-3_4 ◽

2019 ◽

pp. 49-65 ◽

Cited By ~ 2

Author(s):

Pardeep Pankaj ◽

Avinish Tiwari ◽

Pankaj Biswas

Keyword(s):

Thermal Analysis ◽

Stainless Steel ◽

Laser Welding ◽

Co2 Laser ◽

304 Stainless Steel ◽

Thin Plates ◽

Aisi 304 Stainless Steel ◽

Aisi 304 ◽

Transient Thermal Analysis ◽

Transient Thermal

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The effects of morphology of ferrite and non-metallic inclusions on corrosion behaviour of as-cast 304 stainless steel

CORROSION ◽

10.5006/3763 ◽

2021 ◽

Author(s):

Danbin Jia ◽

Liangcai Zhong ◽

Jingkun Yu ◽

Zhaoyang Liu ◽

Yuting Zhou ◽

...

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Corrosion Behaviour ◽

Solidification Process ◽

Inclusion Size ◽

304 Stainless Steel ◽

Experimental Conditions ◽

Quenching Temperature ◽

Δ Ferrite ◽

Metallic Inclusions

The effects of morphology of ferrite and non-metallic inclusions on corrosion resistance of as-cast 304 stainless steel (304 SS) were investigated. With the decrease in quenching temperature from 1723 K to 1648 K, the different microstructures of the as-cast 304 SS were obtained as the following series: austenitic-lathy δ ferrite, austenitic-colony δ ferrite and austenitic-blocky δ ferrite, and the average inclusion size increased. The electrochemical results show that the sample with the microstructure of austenitic- lathy δ ferrite and smaller size inclusions had a higher corrosion tendency and the lower pitting resistance. Furthermore, the effect of morphology and content of ferrite on corrosion resistance was greater than that of inclusion size under the current experimental conditions. Therefore, a promising method was developed to improve the corrosion resistance of as-cast 304 SS by changing the solidification process.

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Study on Laser Welding of Phone Nuts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.815.778 ◽

2013 ◽

Vol 815 ◽

pp. 778-781

Author(s):

Xiao Hong Wu

Keyword(s):

Tensile Strength ◽

Stainless Steel ◽

Laser Pulse ◽

Laser Welding ◽

Pulse Energy ◽

Pulse Width ◽

Peak Power ◽

Laser Pulse Energy ◽

304 Stainless Steel ◽

Power Pulse

Used YAG pulse laser to weld 304 stainless steel nuts, studied about the parameters such as peak power, pulse width, defocus distance impacting on the performance of the joints welded by laser. The studies showed that the tensile strength and torque of the nuts increased as the peak power and the pulse width increased.Burn through in welding easy occur when laser pulse energy is too big, pulse width is too wide or defocus distance is too low.

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Effective hydrogen diffusivities of AISI 304 stainless steel with Ni or Au coating

Materials Testing ◽

10.1515/mt-2020-620608 ◽

2020 ◽

Vol 62 (6) ◽

pp. 593-596

Author(s):

Krittayot Wannapoklang ◽

Sirichai Leelachao ◽

Anchaleeporn W. Lothongkum ◽

Gobboon Lothongkum

Keyword(s):

Stainless Steel ◽

Hydrogen Diffusion ◽

304 Stainless Steel ◽

Phase Identification ◽

Aisi 304 Stainless Steel ◽

Aisi 304 ◽

304 Austenitic Stainless Steel ◽

Hydrogen Assisted Cracking ◽

Stainless Steel Coupon ◽

Effective Hydrogen

AbstractMetallic coatings which provide a hydrogen diffusion barrier are thought to reduce hydrogen assisted cracking on stainless steel. The influence of a metallic layer on the hydrogen migration of AISI 304 stainless steel was investigated using a commercial electroplating layer of Ni and Au on a thin stainless steel coupon. Phase identification was performed using an X-ray diffractometer to determine the average thicknesses, measured from back-scattered scanning electron images. Regarding the ASTM G148-97 practice, the effective hydrogen diffusivities of AISI 304 austenitic stainless steel, nickel and gold were measured as 7.07 × 10-13, 2.72 × 10-14 and 9.64 × 10-16 m2 × s-1, respectively. In this work, a gold layer was found to be most effective for the prevention of hydrogen diffusion when compared with untreated and Ni-plated 304 stainless steel.

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