Effect of tempering temperature on impact energy of AISI 410 martensitic stainless steel at low temperatures

2021 ◽  
Vol 63 (8) ◽  
pp. 699-704
Author(s):  
Kittipat Suwanpatcharakul ◽  
Nithi Saenarjhan ◽  
Nathi Nakthong ◽  
Anchaleeporn Waritswat Lothongkum ◽  
Gobboon Lothongkum

Abstract AISI 410 martensitic stainless-steel specimens were austenitized at 1253 K then oil quenched and tempered at 573, 673, 773 and 923 K for 3600 s. The impact energy of the specimens was tested at 298, 253, 223, 213 K and measured using ASTM E23 standard. After austenitizing and tempering, the microstructure of the specimens showed carbide precipitation. Tempering at 773 K resulted in the highest hardness due to secondary hardening, while tempering at 923 K resulted in the lowest hardness due to brittle carbide precipitation at the grain boundary which caused softening of the matrix by decreasing the solute carbon content. By contrast, the change in impact energy is inversely proportional to the hardness values. The impact surface of specimens tempered at 573, 673 and 773 K revealed transgranular fracture; on the other hand, the impact surface of the specimen tempered at 923 K revealed intergranular fracture. From our experimental results, the appropriate hardening and tempering procedure of AISI 410 for low temperatures applications is selectable.

Author(s):  
Zhenjiang Li ◽  
Yujing Liu ◽  
Ruyi Zhang ◽  
Chao Luo ◽  
Huiping Qi

The evolution of microstructure of low alloy CrMo steel has a great influence on the mechanical properties. Three different tempering heat treatment conditions were made on the material, and the influence of the microstructure on the impact toughness under different test temperatures was studied. The type, morphology, size and distribution of the second phase will evolve with the change of tempering temperature and time. Impact energy of all samples increases gradually from the lower shelf to upper shelf with the testing temperature increasing. In the lower shelf, the fracture is controlled by the crack nucleation. In the ductile-to-brittle transition temperature (DBTT) range, the fracture is determined by the size of the initial crack initiating on the second phase. In the upper shelf, the cleavage fracture is controlled by the propagation of the carbide crack into continuous grains, and the critical event for fracture is the plasticity of the matrix. The scattering of impact energy in DBTT range is caused by the uneven distribution and size of the brittle second phase.


2017 ◽  
Vol 26 (5) ◽  
pp. 096369351702600 ◽  
Author(s):  
Yin Li ◽  
Gan Tian ◽  
Zheng-wei Yang ◽  
Wen-yuan Luo ◽  
Wei Zhang ◽  
...  

The detection and evaluation of low energy impact damage of carbon fibre reinforced polymer (CFRP) laminate were investigated using vibrothermography. To this goal, four specimens were begun with low energy impact with different energies, followed by the detection using vibrothermography. The detection results show that the matrix crack is mainly located closer to the surface opposite to impact, while the delamination is mainly closer to the impact surface. Then, an iterative algorithm based on maximal entropy theory was proposed for thermal image segmentation and on this basis, the damaged area was determined. The obtained results show the damaged area increases with the increase of impact energy and the damaged area and impact energy may present an approximate linear relationship.


Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 408
Author(s):  
Ewa Sjöqvist Persson ◽  
Sofia Brorson ◽  
Alec Mitchell ◽  
Pär G. Jönsson

This study focuses on the impact of solidification on the inclusion morphologies in different sizes of production-scale electro-slag remelting (ESR) and electro-slag remelting under a protected pressure-controlled atmosphere, (PESR), ingots, in a common martensitic stainless steel grade. The investigation has been carried out to increase the knowledge of the solidification and change in inclusion morphologies during ESR and PESR remelting. In order to optimize process routes for different steel grades, it is important to define the advantages of different processes. A comparison is made between an electrode, ESR, and PESR ingots with different production-scale ingot sizes, from 400 mm square to 1050 mm in diameter. The electrode and two of the smallest ingots are from the same electrode charge. The samples are taken from both the electrode, ingots, and rolled/forged material. The solidification structure, dendrite arm spacing, chemical analyzes, and inclusion number on ingots and/or forged/rolled material are studied. The results show that the larger the ingot and the further towards the center of the ingot, the larger inclusions are found. As long as an ingot solidifies with a columnar dendritic structure (DS), the increase in inclusion number and size with ingot diameter is approximately linear. However, at the ingot size (1050 mm in diameter in this study) when the center of the ingot converts to solidification in the equiaxial mode (EQ), the increase in number and size of the inclusions is much higher. The transition between a dendritic and an equiaxial solidification in the center of the ingots in this steel grade takes place in the region between the ingot diameters of 800 and 1050 mm.


Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 773
Author(s):  
Y.H. Guo ◽  
Li Lin ◽  
Donghui Zhang ◽  
Lili Liu ◽  
M.K. Lei

Heat-affected zone (HAZ) of welding joints critical to the equipment safety service are commonly repeatedly welded in industries. Thus, the effects of repeated welding up to six times on the microstructure and mechanical properties of HAZ for AISI 304N austenitic stainless steel specimens were investigated by a Gleeble simulator. The temperature field of HAZ was measured by in situ thermocouples. The as-welded and one to five times repeated welding were assigned as-welded (AW) and repeated welding 1–5 times (RW1–RW5), respectively. The austenitic matrices with the δ-ferrite were observed in all specimens by the metallography. The δ-ferrite content was also determined using magnetic and metallography methods. The δ-ferrite had a lathy structure with a content of 0.69–3.13 vol.%. The austenitic grains were equiaxial with an average size of 41.4–47.3 μm. The ultimate tensile strength (UTS) and yield strength (YS) mainly depended on the δ-ferrite content; otherwise, the impact energy mainly depended on both the austenitic grain size and the δ-ferrite content. The UTS of the RW1–RW3 specimens was above 550 MPa following the American Society of Mechanical Engineers (ASME) standard. The impact energy of all specimens was higher than that in ASME standard at about 56 J. The repeated welding up to three times could still meet the requirements for strength and toughness of welding specifications.


2013 ◽  
Vol 690-693 ◽  
pp. 186-192
Author(s):  
Ho Hua Chung ◽  
Tsong Hsin Chen

This study concerned the influence of the material strength, ductility and impact energy and the relationship of the broken section profile vs. ductile transition brittle where the steel material was treated under different tempering temperature and hardness. Generally after the steel materials, 10B35 coil wire materials which was generally applied to form screws, was treated by quenching and tempering, its hardness ranged from HRC30 to HRC45. The results showed that the elongation rate beyond 20.4% would be proportional to the impact energy with linear relation, but with reverse proportion to the hardness value. The brittle-tough point of the hardness was set around HRC37 after heat treatment in order to balance the strength and the toughness. In addition, the coil wire materials were analyzed from broken section materials showing good toughness; this represented that the area of the cross section radiation layer due to ductile fracture would largely increase. On the contrary, the wire material test fragment with bad toughness represented that the area of the shear layer due to brittle fracture would largely increase as well. As to that material, if its hardness was greater than or equal to HRC37, that material would have an excellent turning danger from transition. At the same time, when the tempering temperature of the wire steel material was set under 4600C and its corresponding central hardness was about HRC37, the distance between two cementite phase layers suddenly increased. This result leaded to the reason why the wire material test fragment was turned into brittleness from ductility. Therefore, when the fastener was manufactured under tempering treatment, avoiding the tempering brittleness temperature range was necessary.


2010 ◽  
Vol 43 ◽  
pp. 651-656
Author(s):  
Ai Xin Feng ◽  
Yu Peng Cao ◽  
Chuan Chao Xu ◽  
Huai Yang Sun ◽  
Gui Fen Ni ◽  
...  

In the experiment, we use pulsed laser to conduct discrete scratching on Ni-containing stainless steel protective coatings to test residual stress situation after the matrix is scratched; then to analyze the the impact of the impact stress wave on coating - substrate bonding strength according to the test results, finally to infer the laser power density range within which it occurs coating failure. The study shows that: after laser discrete scratching, the residual stress of the center of the laser-loaded point on matrix surface gradually reduces when the pulsed laser power density increases. The matrix produces a corresponding residual compressive stress under the laser power density reaches a certain value. The actual failure threshold values are 12.006 GW/cm2, 11.829GW/cm2 and 12.193GW/cm2 measured by the three-dimensional topography instrument testing the discrete scratch point of three groups of samples and verified by using a microscope


2016 ◽  
Vol 138 (3) ◽  
Author(s):  
Zhiwei Chen ◽  
Caifu Qian ◽  
Guoyi Yang ◽  
Xiang Li

In this paper, a series of impact tests on S30403 austenitic stainless steel at 20/−196/−269 °C were performed to determine the effects of cryogenic temperatures on the material properties. Both base plate and welded joint including weld and heat-affected zone were tested to obtain the Charpy impact energy KV2 and lateral expansion rate at the cross section. It was found that when the test temperature decreased from 20 °C to −196 °C or −269 °C, both the Charpy impact energy KV2 at the base plate and welded joint decreased drastically. Specifically, the impact energy KV2 decreased by 20% at the base plate and decreased by 54% at the welded joint from 20 °C to −196 °C, but the impact energy of base plate and welded joint did not decrease, even increased when test temperature decreased from −196 °C to −269 °C. Either at 20 °C or −196 °C, the impact energy KV2 with 5 × 10 × 55 mm3 specimens was about 0.53 times that of the 7.5 × 10 × 55 mm3 specimens, much lower than 2/3, the ratio of two specimens’ cross section areas.


2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Misbahu A Hayatu ◽  
Emmanuel T Dauda ◽  
Ola Aponbiede ◽  
Kamilu A Bello ◽  
Umma Abdullahi

There is a growing interest for novel materials of dissimilar metals due to higher requirements needed for some critical engineering applications. In this research, different dissimilar weld joints of high strength low alloy (HSLA) and 316 austenitic stainless steel grades were successfully produced using shielded metal arc welding (SMAW) process with 316L-16 and E7018 electrodes. Five variations of welding currents were employed within the specified range of each electrode. Other welding parameters such as heat inputs, welding speeds, weld sizes, arc voltages and time of welding were also varied. Specimens for different weld joint samples were subjected to microstructural studies using optical and scanning electron microscopes. The impact toughness test was also conducted on the samples using Izod impact testing machine. The analysis of the weld microstructures indicated the presence of type A and AF solidification patterns of austenitic stainless steels. The results further showed that the weld joints consolidated with E7018 electrode presented comparatively superior impact energy to the weldments fabricated by 316L-16 electrode. The optimum impact energy of E7018-weld joints (51J) was attained at higher welding heat inputs while that of 316L-16-weld joints (35J) was achieved at lower welding heat inputs, which are necessary requirements for the two electrodes used in the experiment. Hence, the dissimilar weld joints investigated could meet requirement for engineering application in offshore and other critical environments.Keywords—Dissimilar metal weld, heat input, impact toughness, microstructures


2011 ◽  
Vol 415-417 ◽  
pp. 813-818 ◽  
Author(s):  
Yong Qing Ma ◽  
Hong Tao Gao ◽  
Yu Fen Liang ◽  
Xiao Jing Zhang

Along with increasing W and Mo contents in Cr-W-Mo-V high alloy medium-upper carbon steels, the maximal hardness of secondary hardening during tempering is increasing gradually and arrives to 66.8HRC, and the congruent quenching temperature and the tempering temperature corresponding to maximal hardness are ascending. The quenching microstructure of experimental steels is matrix and a small quantity of undissolved carbides when the hardness is maximal, wich is corresponding to tempering temperature of remnant austenitic decomposing acutely. The precipitation of M6C and MC carbides was detected, and M7C3 and M3C carbides was detected too. But M23C6 carbide did not appear and M2C carbide was detected undistinguishably. The temperature range of tempering maximal hardness is 500°C-550°C, and an exact temperature is opposite to the mass fraction ratio of equilibrium carbide phases at the temperature. The tempering hardness value can be obtained from HS= a(1+b)/(0.0127a+0.00297), in which a is square root of saturation level of the carbon in the matrix and b is correction factor having something to do with alloy elements of carbide precipitation.


2010 ◽  
Vol 654-656 ◽  
pp. 2515-2518 ◽  
Author(s):  
Yoshitaka Iwabuchi ◽  
Isao Kobayashi

The mechanism of toughness degradation during slow cooling in the austenite range was studied in CA6NM stainless steel, 13% Cr-4% Ni soft martensitic stainless steel. The variation of toughness, fracture mode and microstructural features were examined by means of cooling rate and isothermal heating in the austenite range together with chemical composition. Toughness degradation was referred to as the increases of FATT and intergranular fracture when those steels were cooled slowly after austenitizing and isothermally heated in the austenite range. The embrittlement was found to be related the intergranular fracture and the precipitation of carbide along prior austenite grain boundaries. Its fracture surface was characterized by mosaic-like markings when the carbide precipitation got to increase. Reducing carbon, silicon and phosphorus and increasing molybdenum improve the toughness degradation.


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