scholarly journals Properties Evaluation of the Welded Joints Made by Disk Laser

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2002
Author(s):  
Ján Viňáš ◽  
Janette Brezinová ◽  
Henrich Sailer ◽  
Jakub Brezina ◽  
Miroslav Sahul ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Hsla Steel ◽  
Weld Zone ◽  
High Strength ◽  
Hardness Test ◽  
Weld Interface ◽  
High Rate ◽  
Soft Zone ◽  
Steel Dp600 ◽  
Made In

The process of laser welding of sheets of HSLA (high-strength low-alloy steel), DP600 (dual-phase steel) and TRIP steels was investigated. A weld was successfully made in a double-sided hot-dip galvanized sheet with a thickness of 0.78–0.81 mm using a laser power of 2 kW per pass without any pretreatment of the weld zone. Microstructure studies revealed the presence of martensitic and ferritic phases in the weld zone, which could be associated with a high rate of its cooling. This made it possible to obtain good strength of the weld, while maintaining sufficient ductility. A relationship between the microstructural features and mechanical properties of welds made in the investigated steels has been established. The highest hardness was found in the alloying region of steels due to the formation of martensite. The hardness test results showed a very narrow soft zone in the heat affected zone (HAZ) adjacent to the weld interface, which does not affect the tensile strength of the weld. The ultimate tensile strength of welds for HSLA steel was 340–450 MPa, for DP600 steel: 580–670 MPa, for TRIP steel: ~700 MPa, respectively, exceeding the strength of base steels.

SYNTHESIS AND CHARACTERISATION OF WOVENROVING GLASS MAT FOR EPOXYCOMPOSITES

2020 ◽  
Vol 15 (4) ◽  
Author(s):  
Mahesh Mallampati ◽  
Sreekanth Mandalapu ◽  
Govidarajulu C
Keyword(s):  
Tensile Strength ◽  
Glass Fiber ◽  
Low Cost ◽  
Weight Ratio ◽  
High Strength ◽  
Hardness Test ◽  
Industrial Applications ◽  
Sem Analysis ◽  
Low Thermal Expansion ◽  
Manufacturing Techniques

The composite materials are replacing the traditional materials because oftheir superior properties such as high tensile strength, low thermal expansion, high strength to weight ratio, low cost, lightweight, high specific modulus, renewability and biodegradability which are the most basic & common attractive features of composites that make them useful for industrial applications. The developments of new materials are on the anvil and are growing day by day. The efforts to produce economically attractive composite components have resulted in several innovative manufacturing techniques currently being used in the composites industry. Generally, composites consist of mainly two phases i.e., matrix and fiber. In this study, woven roving mats (E-glass fiber orientation (-45°/45°,0°/90°, - 45°/45°),UD450GSM)were cut in measured dimensions and a mixture of Epoxy Resin (EPOFINE-556, Density-1.15gm/cm3), Hardener (FINE HARDTM 951, Density- 0.94 gm/cm3) and Acetone [(CH3)2CO, M= 38.08 g/mol] was used to manufacture the glass fiber reinforced epoxy composite by hand lay-up method. Mechanical properties such as tensile strength, SEM analysis, hardness test, density tests are evaluated.

An assessment into mechanical properties and microstructural behavior of TIG welded Ti-6Al-4V titanium alloy

2020 ◽  
Vol 10 (3) ◽  
pp. 281-292 ◽  
Author(s):  
Saurabh Dewangan ◽  
Suraj Kumar Mohapatra ◽  
Abhishek Sharma
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Weight Ratio ◽  
High Strength ◽  
Hardness Test ◽  
Content Type ◽  
Ti Alloys ◽  
Microstructure And Mechanical Properties ◽  
Grade 5 ◽  
Selection Of

PurposeTitanium (Ti) alloys are in high demand in manufacturing industries all over the world. The property like high strength to weight ratio makes Ti alloys highly recommended for aerospace industries. Ti alloys possess good weldability, and therefore, they were extensively investigated with regard to strength and metallurgical properties of welded joint. This study aims to deal with the analysis of strength and microstructural changes in Ti-6Al-4V (Grade 5) alloy after tungsten inert gas (TIG) welding.Design/methodology/approachTwo pair of Ti alloy plates were welded in two different voltages, i.e. 24 and 28 V, with keeping the current constant, i.e. 80 A It was a random selection of current and voltage values to check the performance of welded material. Both the welded plates were undergone through some mechanical property analysis like impact test, tensile test and hardness test. In addition, the microstructure of the welded joints was also analyzed.FindingsIt was found that hardness and tensile properties gets improved with an increment in voltage, but this effect was reverse for impact toughness. A good corroboration between microstructure and mechanical properties, such as tensile strength, hardness and toughness, was reported in this work. Heat distribution in both the welded plates was simulated through ANSYS software to check the temperature contour in the plates.Originality/valueA good corroboration between microstructure and mechanical properties, such as tensile strength, hardness and toughness, was reported in this study.

scholarly journals Optimizing the Integrity of Linear Friction Welded Ti2AlNb Alloys

Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 802
Author(s):  
Xi Chen ◽  
Zhao Zhang ◽  
Faqin Xie ◽  
Xiangqing Wu ◽  
Tiejun Ma ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Process Parameters ◽  
Precipitation Hardening ◽  
Weld Zone ◽  
Aging Treatment ◽  
Weld Interface ◽  
Welding Parameters ◽  
Linear Friction ◽  
O Phase

The knowledge of process parameters–weld integrity-aging treatments–tensile property relationship is of great concern for linear friction welded (LFWed) Ti2AlNb-based alloy and requires a systematic characterization. Thus, the Ti2AlNb-based alloy was LFWed under various process parameters and then subjected to different aging treatments. Twelve welding conditions were used to evaluate the weld integrity, showing that impurities and cracks at weld interface can be eliminated under strong welding parameters and the feed rate has the greatest influence on the weld integrity among all process parameters. Relationships among aging temperatures, microstructure evolution, and mechanical properties were investigated. After aging treatment, acicular O phase has precipitated in B2 grains both in the weld zone and thermo-mechanical affected zone (TMAZ). The size of precipitated O phase increases along with the increase of temperature, and the α2 +·O mixtures have finally decomposed into the aggregated acicular O phase. The microhardness and tensile strength of the joints have been enhanced due to the precipitation hardening of O phase and refined grain strengthening after aging treatments.

scholarly journals Effect of Aluminum on Microstructure and Mechanical Properties of Weld Metal of Q960 Steel

Crystals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 26
Author(s):  
Zongxuan Zou ◽  
Zhengjun Liu ◽  
Xingyu Ai ◽  
Dan Wu
Keyword(s):  
Tensile Strength ◽  
Weld Metal ◽  
Impact Energy ◽  
Hsla Steel ◽  
Low Carbon Steel ◽  
High Strength ◽  
Low Carbon ◽  
Cored Wire ◽  
Al Content ◽  
The Impact

High-strength low-alloy (HSLA) steel is used in important steel structural members because of its strength and plastic toughness. Q960 steel is HSLA steel obtained by adding an appropriate amount of alloy elements and quenching and tempering treatment on the basis of ordinary low-carbon steel. This kind of steel has strong hardenability due to the alloy elements added. Cold cracks, embrittlement and softening of the heat-affected zone easily occur after welding. In particular, the low-temperature impact toughness cannot meet the requirements and limits its use. In this paper, self-shielded welding is used to adjust the content of aluminum in flux-cored wire. The relationship between weld metal (WM) microstructure and strength and properties was studied by tensile test and impact test, and the influence mechanism of Al content on weld metal microstructure and properties was analyzed. The results show that when the content of Al is 0.21%, the impact energy at 0 °C~−60 °C is the best, the tensile strength can reach 1035 MPA and the number of pores is small. The size of inclusions in WM is mostly less than 1.0 μm Al2O3 spherical oxide. It can become the center of acicular ferrite (AF) and increase the nucleation probability. However, with the increase of Al content, large irregular AlN inclusions are produced, which reduces the tensile strength and impact energy of the welded joint.

Effect of Different Annealing Process for Microstructure and Properties of 1200MPa HSLA Steel

2015 ◽  
Vol 713-715 ◽  
pp. 2653-2657
Author(s):  
Yu Pei ◽  
Zhe Gao ◽  
Yi Liu ◽  
Shi Qian Zhao ◽  
Chang Yu Xu ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Hsla Steel ◽  
High Strength ◽  
Annealing Process ◽  
Air Cooling ◽  
Low Carbon ◽  
Slow Cooling ◽  
Microstructure And Properties

For C-Si-Mn low carbon HSLA(High Strength Low Alloyed) steel, the influence of microstructure and properties were researched on the different annealing processes. The result showed that the microstructure at room temperature of the steel were polygonal ferrite, island martensite and punctate bainite. With the increase of the annealing temperature, the content of martensite and bainiteincreased and the content of ferrite decreased. Accordingly, tensile strengthincreased from 1069MPa to 1498MPa, and the elongation decreased from 13.8% to 5.1%. With the increase of the overaging temperature, tensile strength decreased from 1315MPa to 1152MPa, and the elongationincreased from8.5% to9.8%. Finally, the optimum annealing process obtained that the annealing temperature was 820°C for 80s, slow cooling to 680°C, water quenching to room temperature, the overaging temperature was 280°C for 300s and air cooling to room temperature. The material obtained higher tensile strength and better elongation.

Numerical and Experimental Investigation on Hot Stamping of Ultra-High Strength Steel

2014 ◽  
Vol 941-944 ◽  
pp. 1720-1725
Author(s):  
Hong Xu ◽  
Mou Rui Zhang ◽  
Li Juan Zhu
Keyword(s):  
High Strength Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Hardness Test ◽  
Side Impact ◽  
Whole Process ◽  
Ultra High Strength Steel ◽  
Metallographic Observation ◽  
Parameters Analysis ◽  
Made In

In the automotive industry, hot stamping of ultra-high strength steel offers the possibility to reduce vehicle weight and enhance safety performance. However, the imperfect technology restricts its application. To investigate the hot stamping technology further, numerical simulation and forming experiment were made in this paper with a door beam as an example. After process parameters analysis, the evolution of sheet during the whole process were predicted through the simulation, according which the microstructure of the part were full martensite and no fracture was produced. A door beam was well-formed in the experiment based on the results of simulation, and then a series of tests as metallographic observation, hardness test, tensile test and side impact test were carried out, studying its performance in practice.

Effect of Flux Constituents and Basicity Index on Mechanical Properties and Microstructural Evolution of Submerged Arc Welded High Strength Low Alloy Steel

2013 ◽  
Vol 738-739 ◽  
pp. 242-246 ◽  
Author(s):  
Sandeep Jindal ◽  
Rahul Chhibber ◽  
N.P. Mehta
Keyword(s):  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Arc Welding ◽  
Hsla Steel ◽  
High Strength ◽  
Submerged Arc Welding ◽  
Strength Increase ◽  
Increase With Increase ◽  
Basicity Index ◽  
Submerged Arc

The application of high strength low alloy (HSLA) steels has been limited by unavailability of suitable joining and filler metals in submerged arc welding (SAW) processes. The present work aims at the design and development of flux for Submerged Arc Welding of HSLA steel. In the work L8 array of Taguchi Design is used to formulate eight types of fluxes to vary basicity index (BI) from 1.26 to 2.81 and to study the effect of flux constituents and basicity index on tensile strength, microhardness and microstructure of the weld metal. Empirical models for ultimate tensile strength and microhardness at the centre of weld versus flux constituents and basicity index have been developed. From the experiments it is found that ultimate tensile strength increase with increase of basicity index with minimum at 1.26 increases upto 2.33 and then further decreases whereas opposite in case of microhardness which is highest at 1.26 and minimum at 1.9. Increase of CaO in the flux increases ultimate tensile strength but microhardness remains unaffected whereas increase of SiO2 decreases ultimate tensile strength but microhardness remains constant. Microhardness decreases critically with increase of CaF2.

Investigation of mechanical properties of nanostructured Al-SiC composite manufactured by accumulative roll bonding

2019 ◽  
Vol 53 (28-30) ◽  
pp. 3951-3961 ◽  
Author(s):  
AF Meselhy ◽  
MM Reda
Keyword(s):  
Experimental Investigation ◽  
Tensile Strength ◽  
Accumulative Roll Bonding ◽  
Shear Fracture ◽  
High Strength ◽  
Hardness Test ◽  
Raw Material ◽  
Composite Sample ◽  
Roll Bonding ◽  
Number Of Passes

To manufacture high-strength, fine dispersed and uniform distribution of Al-5 vol.% SiC composite, accumulative roll bonding process is proposed and applied through this study. The microstructure illustrates and validates a good distribution of SiC reinforced in the Al 1050 matrix. It is found that after eight pass, the mean grain size of the composite sample is 188 nm. It can be concluded from tensile test that by increasing the number of passes the strengths of both Al ARBed and composite samples increase; however, their ductility decreases at the initial accumulative roll bonding pass and then increases. The tensile strength of Al-SiC composite sample is greater than the annealed Al 1050 used as the original raw material by five times. The strengthening of the proposed composite sample occurs due to grain refinement, uniformity, reinforcing role of particles, strain hardening, bonding quality and size of particles. From the hardness test, it is concluded that, after the initial pass, hardness increased quickly, then dwindled and finally saturated by further rolling. Observations discovered that the failure mode in the composite occurs due to the shear fracture. From the experimental investigation, governing equations are derived to describe the effect of the number of accumulative roll bonding passes on the tensile strength and elongation of manufactured metal matrix composite materials. It is found that the tensile strength and elongation can be described as an exponential function of the number of passes. Numerical results from these equations are more consistent with the experimental investigation.

Effect of Retrogression Medium to the Mechanical Properties of Aluminum Alloy 7075

2012 ◽  
Vol 165 ◽  
pp. 6-11 ◽  
Author(s):  
Ng Guan Yao ◽  
Bin Abd Rashid Mohd Warikh ◽  
Buang Zolkepli ◽  
N. Nadiah ◽  
S.C. Leng
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Aluminum Alloy ◽  
Volume Fraction ◽  
Mechanical Test ◽  
High Strength ◽  
Hardness Test ◽  
General Corrosion ◽  
Corrosion Properties ◽  
Aluminum Alloy 7075

Aluminum alloy 7075 is a useful material in industry due to its light weight, high strength, and resistance to general corrosion properties. The drawback of this alloy is its susceptibility to stress corrosion cracking (SCC). From the previous research, it was found that retrogression and re-aging (RRA) heat treatment is able to improve the SCC resistance of this alloy. In this study, the mechanical properties and microstructure alteration due to RRA was studied. First, the tensile specimens are heat treated to T6 and then retrogressed at 165/185/205°C for 10/30 minutes followed by re-aging at 120°C for 24 hours. The retrogression methods are categorized as standard retrogression and oil retrogression. Next, the specimens were gone through tensile test, hardness test, and microstructure characterization by using SEM. From the mechanical test result, the tensile strength and hardness of the alloy decreased upon the increment of retrogression temperature and time. The highest tensile strength of 638.48 MPa was observed at oil retrogress sample at 165°C for 10 minutes which is slight higher than T6 sample. Besides, different phases of precipitation were reviewed by the Kellers etching process. Also, the volume fraction of η phase is increased upon increasing the retrogression temperature and time.

Effect of the Strain Rate on Mechanical Properties and Microstructure of High Strength Low Alloy Steel HC340LA

2012 ◽  
Vol 217-219 ◽  
pp. 467-470
Author(s):  
Xiao Hang Liu ◽  
Wen Jing Yuan ◽  
Hao Bin Tian ◽  
Fa Xi Diao
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Tensile Strength ◽  
Strain Rate ◽  
Alloy Steel ◽  
High Speed ◽  
Hsla Steel ◽  
High Strength ◽  
Static Tension ◽  
Low Alloy Steel

The mechanical properties and microstructure of the high strength low alloy HC340LA were obtained with different strain rate. The research shows that the better plasticity, higher tensile strength and yield ratio can be found in high speed tensile state than in quasi-static tension. The plasticity and tensile strength decrease with the increasing of the strain rate during the high speed tension. With the increasing of the strain rate, the grain size of the ferrite decreases and its distribution is uneven, and the grain boundaries increases. The HSLA steel HC340LA submit to obvious Ductile Frecture mechanism. The size of the dimples is more uniform, bigger and deeper with the strain rate 50 s-1 than with the strain rate 200 s-1. Therefore, the higher strain rate with over strain rate 50 s-1 has less Superscript textcontribution to the improvement of plasticity of the HSLA steel HC340LA.

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