Carbon Steel ASTM Research Articles

Analysis of Dye-Penetrant Test, Tensile Test, and Bending Test Results of Shielded Metal Arc Welding (SMAW) on Carbon Steel ASTM A106 Grade B Pipes in 6G Welding Position at PPSDM Migas Cepu

Analysis of Dye-Penetrant Test, Tensile Test, and Bending Test Results of Shielded Metal Arc Welding (SMAW) on Carbon Steel ASTM A106 Grade B Pipes in 6G Welding Position at PPSDM Migas Cepu

Electrochemical Behavior of Carbon Steel ASTM A36 in Diluted Pregnant Leach Solutions from Electrowinning of Copper

Electrochemical Behavior of Carbon Steel ASTM A36 in Diluted Pregnant Leach Solutions from Electrowinning of Copper

Evolution of Residual Stress, Crystal Orientation, and Texture on Preheating Weld Treatment of Low Carbon Steel ASTM A572 Grade 42

Preheating is one type of heat treatment on the material prior to starting the welding process by increasing the temperature of the material. It is used to reduce the cooling rate during the welding processes to minimize the risk of residual stress and cracking during welding. Besides the benefits of welding, it also has a negative impact, especially on the integrity of the material, because the heating process at high temperatures will cause residual stress, which will affect the mechanical properties, chemical composition, and microstructure of the material, especially on Heat Affected Zone (HAZ). This study aims to analyze the effect of preheating at a temperature of 200 ºC on the welding for ASTM A572 Grade 42 steel with a thickness of 40mm using the SMAW (Shielded Metal-Arch welding) method. ASTM A572 Grade 42 was used in this study with carbon content of less than 0.25%. Based on the results of measurements and analysis using the XRD method, it was found that preheating resulted in reducing the residual stress on both weld metal and HAZ areas. Preheating treatment also moved the peak diffraction to the right side, which means the heat treatment affected compressive residual stress rather than tensile residual stress. For crystal orientation, area [110] has the highest peak diffraction and highest intensity. This area also was found with smaller size crystal size and higher dislocation and microstrain. While bigger crystal size with lower dislocation and microstrain were found in the area [200]. For texture, the highest density was found in the area [200], while the weaker texture was found in the areas [110] and [211]. The texture was influenced by plastic deformation due to atomic structure and its dislocation.

Failure Analysis of Bank-Wall Side Boiler Tube in a Petrochemical Plant

Failure analysis of the petrochemical plant’s bank-wall side boiler tube has been conducted to determine the root cause of tube failure. The tube material is low carbon steel ASTM A178 grade A. Visual examinations of the cracked surface revealed that the fractured surface is flat, without plastic deformation, and several longitudinal and transverse fissures are present. The SEM and optical microscope examinations show that the cracks were intergranular and transgranular. A hydrogen attack caused the intergranular crack, and thermal fatigue produced the transgranular crack. Boiler tube failure was caused by a steam blanket on the sloping tube’s top inner diameter that induced iron oxide deposition and accumulation. Hydrogen was produced after a chemical reaction at the deposit-metal interface between the iron oxide deposit and ingress steam. Local temperature variation on the top part of the sloped tube occurred during the splashing and evaporation of water, promoting thermal fatigue.

Study on mechanical properties of pack carburizing ASTM A36 steel with energizer pomacea canalikulata lamarck shell powder

In the present study material low carbon steel ASTM A36 were treated with pack carburizing with carburizing agent, a mixture of gigantochloa apus (Schult.F.) Kurz charcoal (GAC) and pomacea canalikulata Lamarck shell powder (PCSP). The composition of carburizing agent PCSP-GAC was varied at 10%: 90%, 15%: 85%, and 20%: 80%. The process done at carburizing temperature various 875, 900, 930 ℃ and soaking time for 2 hours. The surface hardness test and an impact test was carried out to determine changes in the surface hardness number and impact toughness. From the results of the study, it was concluded that pack carbrizing with carburizing agent, a a mixture of PCSP and GAC increased the hardness number but decreased the impact toughness of the specimen. The highest hardness number is 537.48 Kg/mm², the lowest impact toughness is 158.33 Joules, at a pack carburizing temperature of 930 ⁰C, the composition of the carburizing agent 20% PCSP : 80% GAC. Microstructural characterization indicates that high toughness of the carburizing steel subjected to the cooling heat treatment process results from a proper multiphase microstructure transition from the surface to the matrix of the steel.

Microstructure and corrosion properties of the AISI 904L weld cladding obtained by the electro slag process

The AISI 904L steel is a superaustenitic stainless steel, which presents a good combination of properties like high strength, weldability, and good corrosion resistance. Despite its wide use in several industrial segments, the literature reporting the performance of claddings deposited with this alloy to improve the corrosion performance of equipment is limited. Based on this scenario, this work evaluates the microstructure and corrosion properties of the AISI 904L steel weld cladding obtained by the electroslag welding (ESW) deposited on a carbon steel ASTM A516 Grade 70. Single layer cladding was deposited on 50 × 400 × 400 mm steel plates with average welding energy of 11.7 kJ/mm to obtain the minimum thickness required. After welding, metallographic examination and corrosion tests were performed on samples removed at 1 and 3 mm parallel to the fusion line. Metallographic characterization was performed by optical and scanning electron microscopy. Cyclic polarization tests in 3.5% NaCl solution were performed at the same positions as the metallographic examinations. The results showed that the austenitic microstructure presenting a low volume fraction of secondary phases provided suitable corrosion results for all conditions studied. It evidences that single layer weld overlays obtained with the AISI 904L steel deposited by the ESW process may be considered an adequate alternative for overlay welding with reduced thicknesses because good results were observed at only 1.0 mm from the fusion line, and this could represent a significant cost reduction.

Effect of DCRP and DCSP Polarity on SMAW Welding on the Depth of Penetration with E7018 Electrodes using Low Carbon Steel ASTM A36

The study aims to determine the level of penetration depth using SMAW (Shielded Metal Arc Welding) Process based on the polarity type of DCRP (Direct Current Reverse Polarity) and DCSP (Direct Current Straight Polarity). This research used ASTM A36 low carbon steel plate with thickness of 6 mm and length of 200 mm, Electrode E7018 LB-52-18 ∅ 3.2 mm, and with current parameters of 90 A, 100 A, 110 A, 120 A and 130 A and 70° welding arc angle. The method used the experimental research. Data collection techniques applied direct observation techniques and descriptive statistical data analysis techniques. Testing the penetration depth of the welds with a macrographic test was conducted by an optical microscope. The test results show that DCRP has more depth than DCSP when the current is 90 A with a difference of 0.38 mm. When the current is 100 A, DCRP is deeper with a difference of 0.312 mm compared to DCSP. The third experiment, with a current of 110 A DCRP, was deeper with a difference of 0.05 mm compared to DCSP. During the fourth and fifth experiments, DCRP was deeper with a difference of 0.21 mm compared to DCSP at 120 A and DCRP was 0.324 mm deeper than DCSP at 130 A. It can be concluded that the effect of DCRP and DCSP polarity on the depth of penetration using E7018 electrodes and ASTM low carbon steel A36, DCRP polarity has a deeper penetration depth compared to DCSP.

Microstructural and Electrochemical Characterization of Zinc Coating onto Low Carbon Steel Substrate

Ordinary steels have poor corrosion resistance in chloride medium leading to a deterioration of their longevity. The present research work focuses on the deposition and characterization of a zinc layer by dip galvanizing onto low carbon steel ASTM A283M-98 in sheet form using different characterization techniques such as optical microscopy, scanning electron microscopy (SEM) coupled to energy dispersion spectrometer (EDS), atomic force microscopy (AFM) and X-ray diffraction (XRD). Optical microscopy and X-ray diffraction analyses of the steel reveal a ferritic microstructure with the presence of a small amount of pearlite. The deposited layer is composed of four Fe–Zn intermetallic phases, namely eta (η), zeta (ζ), delta (δ), and gamma (Γ). The electrochemical study in 0.5M NaCl medium indicate an enhancement of the corrosion resistance of ASTM A283M-98 steel coated with Fe–Zn multi-phased layer, characterized by a decrease in corrosion current (Icorr = 3.36μA/cm2) and corrosion rate (Cr = 0.29mm/year) compared to the bare steel (Icorr = 12.29μA/cm2 and Cr= 0.72mm/year).

Fatigue Corrosion Behavior of Friction Welded Dissimilar Joints in Different Testing Conditions

Our study will be focused on stainless steel AISI 304—carbon steel ASTM A105 joints obtained by rotary friction welding and on their fatigue corrosion behavior in different testing environments. As a first thing, the joints will be characterized by microscopy and electrochemical techniques. The manuscript will then describe the optimization of the experimental setup and the validation of the testing procedure. After that, the fatigue behavior of the joints will be tested in different aggressive environments. This study pointed out that it is possible to build a simple and low-cost setup for the study of fatigue corrosion behavior of dissimilar joints while exploiting in situ electrochemical measurements to follow the fatigue corrosion process.

Study the Effect of Welding Position and Plate Thickness to the Mechanical and Microstructural Properties of the TIG Dissimilar Metal Welded between Carbon Steel ASTM A36 and Stainless Steel 304 Plates

Dissimilar metal welding was mostly done to optimize the application and engineering requirements with economic considerations. Weld microstructures greatly influenced the mechanical properties of welded joints. The investigations were carried out to evaluate the microstructural and mechanical properties of dissimilar weldment between carbon steel ASTM A36 and austenitic stainless steel 304 with a variation of welding position (1G, 2G, 3G) and weld thickness (6 mm to 12 mm) joints by TIG welding. A detailed analysis was conducted on the weld zone composition, the microstructural, and mechanical properties. The results show that the welding position and thickness of the weld joints influenced the microstructure both in HAZ and weld metal. Size, distribution, and orientation of microstructure were improved and more uniform with increasing of welded joint thickness. In HAZ carbon steel, GB ferrite was dominant, especially for the flat welding position (1G), while for the horizontal position (2G) and the vertical welding position (3G) showed other structures such as Widmanstaten ferrite, hard-structures like martensite and bainite. In the region near the fusion line and the weld metal, the chemical composition changed due to thermal convection, diffusion, and macro-segregation caused by penetration of liquid metal carbon steel into the weld pool. SEM/EDS results indicated diffusion of carbon from carbon steel A36 to stainless steel 304 and formed the hard-structure along the fusion line. The mechanical test results showed that the tensile test breaking point occurred in the parent metal of carbon steel A36. The bending test results showed very high stress on the face side of the welding joint, and there are no cracks from the bending test result. Vickers hardness testing showed that the hardness distribution increased from the carbon steel HAZ to the stainless steel HAZ, and the maximum hardness has achieved the value of 297 Hv at the fusion line of stainless steel 304.

Metallurgical Characterization of the Interfaces in Steel Plates Clad with Austenitic Steel or High Ni Alloys by Hot Rolling

An integrated experimental-theoretical approach to the metallurgical characterization of the interfaces in steel plates clad by hot rolling is proposed. Three different couplings of materials have been studied: ASTM A 515 Gr.60 low carbon steel clad with austenitic stainless steel AISI 304L; extra low carbon steel ASTM A283 clad with high Ni content Alloy 59; and, low carbon steel AISI 1010 clad with Cu-Ni Monel 400. Experimental investigations, which are addressed to analyse the microstructural changes near the interfaces and identify the present phases, have been carried out through scanning electron microscopy (SEM) observations, microanalytical measurements by energy dispersive spectroscopy (EDS), and Vickers microhardness tests. In all of the cases examined, the zones that are affected by detrimental microstructural changes results in being considerably less thick than the overall cladding layer. Simulations that are based on theoretical diffusion modelling have been integrated to the experimental characterization by introducing a cladding parameter that acts on the diffusion bonding efficiency, in order to evaluate the effects of process temperature and time variations on diffusion bonding efficiency and stability. In particular, this analytical investigation has shown how the shorter is the duration of the diffusion transient and the higher the temperature, the lower results the sensitivity of the diffusion processes to temperature fluctuations.

Corrosion and biocorrosion in carbon steel

The present study had as objective to evaluate the corrosion and biocorrosion in carbon steelASTM A immersed in a biphasic system containing Diesel S tap water in proportions of under static conditions over days Scanning electron microscopy SEM techniques were used to monitor these processes The results indicated that there was localized corrosion especially on surfaces that were immediately below the diesel water interface where corrosion products and biofilm adherence were formed Therefore the results revealed that the presence of water in the diesel can be an aggravating factor in the processes of corrosion and biocorrosion

Relationship between Compressive Residual Stress Relaxation and Microhardness Reduction after Cyclic Loads on Shotpeened ASTM A516 Grade 70 Steel

Shot peening process is a cold performed function to enhance the mechanical properties which is widely used in many industries. This process introduces compressive residual stress which was proven to increase the fatigue life, geometry stability and corrosion resistance. However, the benefit of the residual stress is still unstable due to the relaxation during the operation. This paper will study on the trend of the relaxation of residual stress against cyclic loading as well as the change in the hardness. The material used in this study is carbon steel ASTM A516/ SA 516 Grade 70. Shot peening process with steel shots was applied to the samples to introduce compressive residual stress in the samples. Cyclic load was applied to samples after shot peening process with low load of 52Mpa (20% of Yield Strength) and high load of 208Mpa (80% of Yield Strength). The measurement of residual stress using X-Ray diffraction and hardness test was done on the samples to study the trend of the relaxation of residual stress and the change in hardness values. The result shows that more relaxation of residual stress occurs if the applied cyclic load is higher. The change of hardness trend is found non-sequenced in this study due to random coverage of shot peening.

Biocorrosion on Surface of ASTM A283 Carbon Steel, Exposed in Diesel S10 and Tap Water

This paper sets out to evaluate the corrosion and biocorrosion of carbon steel ASTM A283 exposed to a Diesel S10 oil/tap water system under static conditions for 90 days. The following analyzes were performed: physico-chemical in tap water, sulfur content in Diesel S10 and quantification of sessile microorganisms in the biofilm formed on the metal. To monitor the corrosion process, mass loss, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), confocal laser microscopy and X-ray diffraction (XRD) were performed. There were changes in the composition of the medium, correlated with the formation of corrosion and biofilm products. There was biodegradation of the fuel, which in contact with water influenced the development of microorganisms. Moreover, the corrosion rate was classified as moderate, the main form of corrosion being seen to be local alveolar corrosion. Therefore, the results revealed that water in diesel oil can be an aggravating factor in the process of corrosion and biocorrosion.

Bio-Inhibitor on Corrosion Rate of ASTM A53 Steel in Marine Environment

There are many methods to prevent the corrosion process. One of them is corrosion inhibitors usage. Inhibitor divided into two types, there are organic inhibitor and non-organic inhibitor. Organic inhibitor could be obtained by extracting some materials which exist in nature. In this research, bio-inhibitors were made from rambutan (Nephelium lappaceum) peel, banana (Musa acuminata Colla) peel, mango (Mangifera indica L.) leaves and papaya (Carica papaya)leaves. The determination of corrosion rate used weight loss method. The material of carbon steel ASTM A53 was used in the research. The salinity of artificial seawater was 35 ‰. The results showed that corrosion rate on carbon steel ASTM A53 was 0.2172 mpy at mango leaves and the efficiency of those inhibitor was 44.5%. The corrosion rate carbon steel ASTM A53 was 0.2436 mpy for corrosion rate and 37.8% of inhibitor efficiency when it used papaya leaves as bioinhibitor. Meanwhile, it reached 0.2739 mpy and 0.2812 mpy of corrosion rate for banana peel and rambutan peel, respectively. The efficiency of inhibitor were 30% and 28.2% for banana peel and rambutan peel, respectively. The corrosion rate on carbon steel ASTM A53 without inhibitor was 0.3914 mpy. Based on the microstructure results, all specimens in all variation of treatments showed pitting corrosion and uniform corrosion on specimen. In conclusion, mango leaves, papaya leaves, banana peel and rambutan peel have potentially to be used as bio-inhibitor to decrease the corrosion rate in marine environment.

A Study of Characteristics on the Dissimilar Metals (Alloy steel : A387 Gr. 91 - Carbon Steel : A516 Gr. 70) Welds Made with FCA Multiple Layer Welding: Part 2

Characteristics of dissimilar metal welds between alloy steel ASTM A387 Gr. 91 and carbon steel ASTM A516 Gr.70 made with Flux cored arc welding(FCAW) have been evaluated in terms of microstructure, mechanical strength, chemical analysis by EDS as well as corrosion test. Three heat inputs of 15.0, 22.5, 30.0kJ/cm were employed to make joints of dissimilar metals with E71T-1C wire. Post-weld heat treatment was carried out at 750°C for 2.5 h. Based on microstructural examination, Intragranular polygonal ferrite and grainboundary ferrite were formed only in first layer of weld metal. Another layers consisted of acicular ferrite and Widmannstӓtten ferrite. The amount of acicular ferrite was increased with decreasing heat input and layer. Heat affected zone of alloy steel showed the highest hardness due to the formation of tempered martensite and lower bainite. Lower and upper bainite were formed in heat affected zone of carbon steel. Tensile strengths of dissimilar metal welds decreased with increasing heat inputs. Dissimilar metal welds showed a good hot cracking resistance due to the low HCS index below 4. The salt spray test of dissimilar metals welds showed that the weight loss rate by corrosion below 170 hours was decreased with increasing heat inputs due to the increase of the amount of acicular ferrite. Key words: Dissimilar weld, FCA multipass, Acicular ferrite, Widmannstӓtten ferrite

Evaluation of the AISI 904L Alloy Weld Overlays Obtained by GMAW and Electro-Slag Welding Processes

The use of superaustenitic stainless steels (SASS) as an overlay replacement for nickel-based alloys can be an interesting alternative for the oil and gas industries, due to its lower cost, when compared to superalloys. Usually, the deposition is made with several welding passes by using conventional arc welding processes, such as gas tungsten arc welding (GTAW) or gas metal arc welding (GMAW) processes. In this respect, electro-slag welding (ESW), which promotes high heat inputs and low dilution of the welds, can also be attractive for this application, as it provides a higher productivity, once only one layer is needed for the deposition of the minimum thickness required. The present work evaluates the behavior of an AISI 904L SASS weld overlay deposited on a carbon steel ASTM A516 Grade 70 by ESW and GMAW processes. Both as-welded and heat-treated conditions were evaluated and compared. A multipass welding by GMAW process with three layers and 48 passes was performed on 12.5 × 200 × 250 mm steel plates with average welding energy of 1.0 kJ/mm. For ESW process, only one layer was deposited on 50 × 400 × 400 mm steel plates with average welding energy of 11.7 kJ/mm. After welding, a post-weld heat treatment (PWHT) at 620 °C for 10 h was performed in half of the steel plate, in order to allow the comparison between this condition and the as-welded one. For both processes, the austenitic microstructure of the weld deposits was characterized by optical microscopy and scanning electron microscopy with electron backscatter diffraction. A low proportion of secondary phases were observed in all conditions, and the PWHT did not promote significant changes on the hardness profile. Martensite for GMAW process and bainite for ESW process were the microstructural constituents observed at the coarse grain heat-affected zone, due to the different cooling rates. For ESW process, no evidences of partially diluted zones were found. As a consequence of the microstructural findings, the hardness results for ESW were lower than those usually observed for other electric arc welding processes. In addition, specimens subject to bending tests performed in accordance with the current standards used for qualification of welding procedures were approved. These evidences allow the conclusion that the ESW process can provide deposits with high quality despite the high welding energy levels, in order to achieve the desired productivity, being an interesting alternative for AISI 904L weld overlays.

스테인리스강 STS 316L과 탄소강 A516-70의 이종금속 GTA 용접부 특성에 대한 연구

Abstract Characteristics of dissimilar metal welds between STS 316L and carbon steel ASTM A516 Gr.70 made with GTAW have been evaluated in terms of microstructure, ferrite content, chemical analysis, hardness and corrosion resistance. Three heat inputs of 9.00, 11.25, 13.00kJ/cm were employed to make joints of dissimilar metals with ER309 wire. Based on microstructural examination, the amount of vermicular type of δ-ferrite was increased with increasing heat input due to the increase of Creq /Nieq in the second layer of welds. Based on the EDX analysis of weld metals, Cr and Ni content in the 2nd layer increased while those content in the first layer of welds decreased with heat inputs. Cellular solidification mode in the 1st layer and dendritic solidification mode in the 2nd layer due to different cooling rates were prevailed, respectively. Heat affected zone which formed hard microstructure showed higher hardness than the weld metal. The salt spray test of dissimilar metals weld joints showed that the carbon steel surfaces only corroded. The weight loss rate due to corrosion increased up to 100hours but it decreased above 100 hours. There was little difference in the weight loss caused by corrosion regardless of heat inputs.Key Words : Dissimilar metals welding, GTAW, δ-ferrite, Vermicular ferrite, Corrosion, Heat input

슈퍼듀플렉스 스테인리스강 UNS S32750과 탄소강 A516-70의 이종금속 FCA 용접 특성에 대한 연구

The metallurgical and mechanical characteristics, toughness and corrosion resistance of dissimilar welds between super duplex stainless steel UNS S32750 and carbon steel ASTM A516Gr.70 have been evaluated. Three heat inputs of 21.12, 24.00, 26.88kJ/cm were employed to make joints of dissimilar metals with flux cored arc welding(FCAW). Based on microstructural examination, vermicular ferrite was formed in the first layer of weld at low heat input(21.12kJ/cm) and <TEX>$Cr_{eq}/Ni_{eq}$</TEX> of 1.61 while acicular ferrite was formed in last layer of weld at high heat input(26.88kJ/cm) and <TEX>$Cr_{eq}/Ni_{eq}$</TEX> of 1.72. Ferrite percentage in dissimilar welds was lowest in the first layer of weld regardless of heat inputs and it gradually increased in the second and third layers of weld. Heat affected zone showed higher hardness than the weld metal although reheated zone showed lower hardness than weld metal due to the formation of secondary austenite. Tensile strengths of dissimilar welds increased with heat input and there was 100MPa difference. The corrosion test by ferric chloride solution showed that carbon steel had poor corrosion resistance and pitting corrosion occurred in the first layer(root pass) of weld due to the presence of reheated zone where secondary austenite was formed. The salt spray test of carbon steel showed that the surface only corroded but the amount of weight loss was extremely low.

Elucidating Corrosion Performance of Weld in CO&lt;sub&gt;2&lt;/sub&gt; Corrosion Environment

Weld corrosion is suspected to contribute to localized corrosion failure of pipelines in CO2 environment. Some studies on the mitigation of the weld corrosion had been focused on weld metal micro-alloying producing cathodic weld metal but with mixed success result. The inconsistent result is due to lack of understanding on the mechanism of weld corrosion in this corrosive CO2 environment. This paper presents the study of the possibility of weld corrosion from the galvanic and self-corrosion effects of welded low carbon steel ASTM 106 B pipeline in pH 5-CO2 saturated environment at 25 °C and 60 °C under stagnant condition. The weld region samples were prepared by metallography method to identify the parent metal (PM), heat affected zone (HAZ) and weld metal (WM) microstructures. Galvanic current was measured for each weld region by zero resistance ammeters (ZRA) and self-corrosion rate was measured by electrochemical impedance spectroscopy (EIS). The total corrosion rate was determined from the summation of galvanic corrosion and self-corrosion for all weld regions. From the galvanic current test result, weld metal was found to be anodic for both 25 °C and 60 °C. Weld metal also experienced the highest self-corrosion rate in the range of 40-98% as compared to parent metal and HAZ region for both 25 °C and 60°C. The total corrosion rate was mainly contributed by the self-corrosion rates and the contribution from galvanic corrosion was considered insignificant. Possible preferential weld corrosion can occur on weld metal region due to differential self-corrosion rates of each weld regions.