Welding Technology of Ultra-Low Carbon and Nitrogen Ferrite Stainless Steel

2010 ◽  
Vol 654-656 ◽  
pp. 354-357
Author(s):  
Bao Sen Wang ◽  
Shuang Chun Zhu ◽  
Xia Ning Ye
Keyword(s):  
Stainless Steel ◽  
Heat Affected Zone ◽  
Heat Input ◽  
Welding Process ◽  
Low Carbon ◽  
Carbon And Nitrogen ◽  
Welding Joint ◽  
High Toughness ◽  
Process Gas ◽  
Welding Technology

Weldability of ultra low carbon and nitrogen, low chromium ferrite stainless steel is analysed by using Thermol-cal software and welding metallurgy. Eembrittlement of welding joint is the failure reason during application of ultra low carbon and nitrogen 12% chromium FSS. Comparing welding joint performance of different welding process, Gas Metal Arc Weldinng with high toughness welding material and proper welding heat input is economical and feasible welding process. Controlling growth of ferrite grain is the key to improve toughness of the heat affected zone (HAZ). Presence of titanium carbides or nitrides and the amount of martensite located along ferrite grain intergranular boundaties are very important for toughness of HAZ in low chromium FSS. It was found that the best size of Ti(C/N) grain is 2-5μm and content of martensite is 40%.

scholarly journals Development and Comparison of Quantitative Phase Analysis for Duplex Stainless Steel Weld

2018 ◽  
Vol 62 (3) ◽  
pp. 247-253 ◽  
Author(s):  
Balázs Varbai ◽  
Timothy Pickle ◽  
Kornél Májlinger
Keyword(s):  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Heat Affected Zone ◽  
Heat Input ◽  
Welding Process ◽  
Phase Ratio ◽  
Quantitative Phase Analysis ◽  
Point Count ◽  
Count Method ◽  
Point Count Method

In duplex stainless steels the ideally 1:1 ratio of austenite-to-ferrite phases ensures the outstanding mechanical and corrosion properties compared to other, conventional stainless steel grades. However, this phase balance can be easily shifted to a mostly austenitic or mostly ferritic microstructures, depending on the welding process and heat input. In order to determine the phase ratio, several methods are available to use, such as Feritscope measurements, ASTM E562 manual point count method (on metallographic images) or quantitative image analysis. From these methods, Feritscope measurements cannot be applied to determine phase quantification in the narrow heat affected zone of duplex stainless steel welds – because of the very limited heat input. The manual point count method is very dependent of the assessor and cannot be automated. In this paper a histogram-based image analyzing process was developed, using Beraha's etchant solution. The results were compared to Feritscope measurements and a very good correlation (R2 = 0.9995) was found. This method will give the ability to easily and automatically measure phase ratio in weld metal, heat affected zone or in subsurface regions of multi-pass welds.

Influence of Thermal Simulated and Real Tandem Submerged Arc Welding Process on the Microstructure and Mechanical Properties of the Coarse Grained Heat Affected Zone

2011 ◽  
Vol 110-116 ◽  
pp. 3191-3198
Author(s):  
Sadegh Moeinifar
Keyword(s):  
Grain Boundaries ◽  
Heat Affected Zone ◽  
Heat Input ◽  
Arc Welding ◽  
Welding Process ◽  
Submerged Arc Welding ◽  
Rolled Plate ◽  
Arc Welding Process ◽  
Submerged Arc ◽  
Tandem Submerged Arc Welding

The high-strength low-alloy microalloyed steel was procured as a hot rolled plate with accelerated cooling. The Gleeble thermal simulated process involved heating the steel specimens to the peak temperature of 1400 °C, with constant cooling rates of 3.75 °C/s and 2 °C/s to room temperature. The four-wire tandem submerged arc welding process, with different heat input, was used to generate a welded microstructure. The martensite/austenite constituent appeared in the microstructure of the heat affected zone region for all the specimens along the prior-austenite grain boundaries and between bainitic ferrite laths. The blocky-like and stringer martensite/austenite morphology were observed in the heat affected zone regions. The martensite/austenite constituents were obtained by a combination of field emission scanning electron microscopes and image analysis software The Charpy absorbed energy of specimens was assessed using Charpy impact testing at-50 °C. Brittle particles, such as martensite/austenite constituent along the grain boundaries, can make an easy path for crack propagation. Similar crack initiation sites and growth mechanism were investigated for specimens welded with different heat input values.

scholarly journals Study on the Effect of Heat-Input on the Thickness of the Heat-Affected Zone of the SUS316L Steel Welded Joint by Numerical Simulation

2021 ◽  
Vol 31 (5) ◽  
pp. 68-74
Keyword(s):  
Numerical Simulation ◽  
Heat Affected Zone ◽  
Heat Input ◽  
Welded Joint ◽  
Plate Thickness ◽  
Great Influence ◽  
Thickness Direction ◽  
Welding Joint ◽  
Simulation Results ◽  
The Right

The thickness of the heat-affected zone (HAZ) has a great influence on the strength of the welded joint, so one of the important tasks is to control the HAZ to a small enough level, through using the suitable heat-input (qd). In this study, the authors use SYSWELD software to compute and build a relationship between the heat-input and the thickness of the heat-affected zone in the plate thickness direction to find the right heat-input for researched welding joint. The simulation results show that when welding the root pass with qd > 552 J/mm and the cap pass with 754 J/mm < qd < 1066 J/mm, the thickness of HAZ were increased with a function almost linearly.

scholarly journals Study the Effect of Welding Heat Input on the Microstructure, Hardness, and Impact Toughness of AISI 1015 Steel

2018 ◽  
Vol 14 (1) ◽  
pp. 118-127 ◽  
Author(s):  
Emad Kh. Hamd ◽  
Abbas Sh. Alwan ◽  
Ihsan Khalaf Irthiea
Keyword(s):  
Corrosion Rate ◽  
Weld Joint ◽  
Heat Input ◽  
Plate Thickness ◽  
Welding Process ◽  
Welding Current ◽  
Low Carbon ◽  
Mig Welding ◽  
The Impact ◽  
Weld Heat

In the present study, MIG welding is carried out on low carbon steel type (AISI 1015) by using electrode ER308L of 1.5mm diameter with direct current straight polarity (DCSP). The joint geometry is of a single V-butt joint with one pass welding stroke for different plate thicknesses of 6, 8, and 10 mm. In welding experiments, AISI 1015 plates with dimensions of 200×100mm and edge angle of 60o from both sides are utilized. In this work, three main parameters related to MIG welding process are investigated, which are welding current, welding speed, heat input and plate thickness, and to achieve that three groups of plates are employed each one consists of three plates. The results indicate that increasing the weld heat input (through changing the current and voltage) leads to an increase in widmanstatten ferrite (WF), acicular ferrite (AF) and polygonal ferrite (PF) in FZ region, and a reduction in grain size. It is observed that the micro-hardness of welded AISI 1015 plate increases as the weld heat input decreases. As well as increasing the weld heat input results in an increase in the width of WM and HAZ and a reduction in the impact energy of the weld joint of AISI 1015 at WM region. Also, it is noted the corrosion rate of weld joint increases with increase of Icorr due to increasing in welding current (heat input), corrosion rate increased up to (0.126µm/yr.) with increasing of heat input up to (1.27 KJ/mm).  

scholarly journals On the Refining Condition of Extremely Low Carbon and Nitrogen Stainless Steel in VOD Process

1977 ◽  
Vol 63 (13) ◽  
pp. 2077-2086 ◽  
Author(s):  
Hiroyuki KATAYAMA ◽  
Hiroyuki KAJIOKA ◽  
Makoto INATOMI ◽  
Fusao TANAKA ◽  
Hideto HOSODA
Keyword(s):  
Stainless Steel ◽  
Low Carbon ◽  
Carbon And Nitrogen

Effect of the FCAW Welding Process and Post Weld Heat Treatment on the Properties and Microstructure of the Weld Joints of Heat Treated 4330V Steel

2015 ◽  
Vol 809-810 ◽  
pp. 437-442
Author(s):  
Jacek Górka ◽  
Michał Miłoszewski
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Weld Metal ◽  
Heat Input ◽  
Large Diameter ◽  
Welding Process ◽  
Post Weld Heat Treatment ◽  
High Toughness ◽  
Interpass Temperature ◽  
Weld Heat

4330V is a high strength, high toughness, heat treatable low alloy steel for application in the oil, gas and aerospace industries. It is typically used for large diameter drilling parts where high toughness and strength are required. The research describes the effect of preheat temperature, interpass temperature, heat input, and post weld heat treatment on strength, hardness, toughness, and changes to microstructure in the weld joint. Welding with the lower heat input and no post weld heat treatment resulted in optimal mechanical properties in the weld metal. Austempering at 400 °C resulted in optimal mechanical properties in the HAZ. Increasing preheat and interpass temperature from 340 °C to 420 °C did not improve Charpy V-notch values or ultimate tensile strength in the weld metal or heat affected zones. The higher temperature increased the width of the heat affected zone. Austempering at 400 °C reduced HAZ hardness to a level comparable to the base metal. Both tempering and austempering at 400 °C for 10 hours reduced toughness in the weld metal.

Sign in / Sign up

Export Citation Format

Share Document