Effect of over Tempering at UHSLA Steel ARMOX 500

2014 ◽  
Vol 875-877 ◽  
pp. 1324-1328
Author(s):  
Igor Barényi ◽  
Peter Lipták ◽  
Sergej Vojtovič
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Production Process ◽  
High Hardness ◽  
Specific Production ◽  
Cooling Process ◽  
Secondary Processing ◽  
Degradation Of Mechanical Properties ◽  
Quenching And Tempering

ARMOX steels are armored steels used for protect devices and facilities against blasts and explosions. Due to this purpose the ARMOX 500 steel has excellent mechanical properties as are high hardness, tensile strength and good toughness. These properties result from specific production process finished with rolling ant then quenching and tempering. The producer of ARMOX steels recommend their secondary processing (cutting, welding, shaping) at temperatures lower than 200°C due to over tempering and degradation of mechanical properties in heat affected areas. The paper describes the mechanism and reason of this degradation including the simulation of cooling process with ARMOX 500 steel.

scholarly journals Superior Mechanical Behavior and Fretting Wear Resistance of 3D-Printed Inconel 625 Superalloy

2018 ◽  
Vol 8 (12) ◽  
pp. 2439 ◽  
Author(s):  
Yong Gao ◽  
Mingzhuo Zhou
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Wear Resistance ◽  
Additive Manufacturing ◽  
High Hardness ◽  
Fretting Wear ◽  
Inconel 625 ◽  
3D Printed ◽  
Inconel 625 Superalloy ◽  
Electron Beam Selective Melting

Additive manufacturing (AM) nickel-based superalloys have been demonstrated to equate or exceed mechanical properties of cast and wrought counterparts but their tribological potentials have not been fully realized. This study investigates fretting wear behaviors of Inconel 625 against the 42 CrMo4 stainless steel under flat-on-flat contacts. Inconel 625 is prepared by additive manufacturing (AM) using the electron beam selective melting. Results show that it has a high hardness (335 HV), superior tensile strength (952 MPa) and yield strength (793 MPa). Tribological tests indicate that the AM-Inconel 625 can suppress wear of the surface within a depth of only ~2.4 μm at a contact load of 106 N after 2 × 104 cycles. The excellent wear resistance is attributed to the improved strength and the formation of continuous tribo-layers containing a mixture of Fe2O3, Fe3O4, Cr2O3 and Mn2O3.

scholarly journals Effect of Heat-treatment Parameters of Cast Iron GJS-X350NiMnCu7-3-2 on its Structure and Mechanical Properties

2017 ◽  
Vol 17 (1) ◽  
pp. 121-126 ◽  
Author(s):  
D. Medyński ◽  
A. Janus ◽  
S. Zaborski
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Cast Iron ◽  
High Hardness ◽  
Spheroidal Graphite ◽  
Air Cooling ◽  
Material Hardness ◽  
The Matrix ◽  
Lower Material

Abstract The paper presents influence of soaking parameters (temperature and time) on structure and mechanical properties of spheroidal graphite nickel-manganese-copper cast iron, containing: 7.2% Ni, 2.6% Mn and 2.4% Cu. Raw castings showed austenitic structure and relatively low hardness (150 HBW) guaranteeing their good machinability. Heat treatment consisted in soaking the castings within 400 to 600°C for 2 to 10 hours followed by air-cooling. In most cases, soaking caused changes in structure and, in consequence, an increase of hardness in comparison to raw castings. The highest hardness and tensile strength was obtained after soaking at 550°C for 6 hours. At the same time, decrease of the parameters related to plasticity of cast iron (elongation and impact strength) was observed. This resulted from the fact that, in these conditions, the largest fraction of fine-acicular ferrite with relatively high hardness (490 HV0.1) was created in the matrix. At lower temperatures and after shorter soaking times, hardness and tensile strength were lower because of smaller degree of austenite transformation. At higher temperatures and after longer soaking times, fine-dispersive ferrite was produced. That resulted in slightly lower material hardness.

scholarly journals Research on the Microstructures and Mechanical Properties of Bainite/Martensite Rail Treated by the Controlled-Cooling Process

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3061 ◽  
Author(s):  
Jiajia Qiu ◽  
Min Zhang ◽  
Zhunli Tan ◽  
Guhui Gao ◽  
Bingzhe Bai
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Tensile Strength ◽  
Impact Toughness ◽  
Electron Backscatter Diffraction ◽  
Microstructural Characterization ◽  
Cooling Process ◽  
Controlled Cooling ◽  
Transmission Electron ◽  
Backscatter Diffraction

A bainite/martensite multiphase rail is treated by the controlled-cooling process with different finish-cooling temperatures. The simulated temperature–time curves of the position of 5 mm and 15 mm below the rail tread (P5 and P15) express different trends. P5 has greater impact toughness and lower tensile strength than P15. Microstructural characterization was carried out by conducting scanning electron microscopy, X-ray diffraction, electron backscatter diffraction, and transmission electron microscopy. The greater tensile strength is due to the dispersed ε-carbides hindering the movement of dislocations. The greater impact toughness is attributed to the filmy retained austenite and the smaller effective grain with high-angle boundary. Finite element modeling (FEM) and microstructural characterization reasonably explain the changes of mechanical properties. The present work provides experimental and theoretical guidance for the development of rail with excellent mechanical properties.

Preparation of heavy-section ductile iron with improved mechanical properties through quenching and tempering

2020 ◽  
Vol 111 (5) ◽  
pp. 385-391
Author(s):  
Lifeng Tong ◽  
Qingchuan Zou ◽  
Jinchuan Jie ◽  
Tingju Li ◽  
Zhixin Wang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Ductile Iron ◽  
High Strength ◽  
Iron Matrix ◽  
Heavy Section ◽  
Pearlite Content ◽  
Higher Temperature ◽  
Quenching And Tempering ◽  
Tempering Time

Abstract In order to prepare heavy-section ductile iron with high strength and excellent elongation, a series of quenching- tempering experiments was conducted. A relationship between quenching-tempering time and temperature and the contents of martensite and pearlite was established by adjusting different quenching mediums and process parameters, and different microstructures in the iron matrix led to different mechanical properties. The content of martensite in the iron matrix reached over 94% after quenching at 880°C or a higher temperature. Further, the pearlite content could reach over 91% after tempering at 570°C or a higher temperature, thus resulting in improved mechanical properties. The investigated ductile iron yielded mechanical properties of a tensile strength of 970 MPa and an elongation of 6% after quenching in water at 880°C and tempering at 570°C. This will provide more possibilities for the application of heavy-section ductile iron parts.

Water Lubricated Bearing Molding Technology Impact on Bearing Bush Material Performance

2011 ◽  
Vol 382 ◽  
pp. 408-413
Author(s):  
Jin Min Peng
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Production Process ◽  
Induction Period ◽  
Bearing Material ◽  
Molding Temperature ◽  
Time Points ◽  
And Performance

Water lubricated plastic alloy bearing molding technology determines the mechanical properties and performance of the product. The influence of molding temperature and time are significant on the performance of water lubricated bearing. The experiment selected five vulcanization temperatures from 110°C-190°C, and five time points from 5-25min to assess their influence on the tensile strength, stretching strength and abradability of bearing material. The corelation between temperature and time is analyzed and a vulcanization curve of plastic alloy production in the situation of 170°C (vulcanization temperature), 2Mpa (vulcanization pressure). The curve realizes a long vulcanization induction period at a fast vulcanization speed with a broad vulcanization plateau that reduces the vulcanization time in the production process and enhances efficiency massively.

scholarly journals Estimation of Austenitizing and Multiple Tempering Temperatures from the Mechanical Properties of AISI 410 using Artificial Neural Network

2018 ◽  
Vol 7 (4.19) ◽  
pp. 778
Author(s):  
Abdul Kareem F. Hassan ◽  
Qahtan A. Jawad
Keyword(s):  
Neural Network ◽  
Mechanical Properties ◽  
Heat Treatment ◽  
Artificial Neural Network ◽  
Tensile Strength ◽  
Regression Analysis ◽  
Impact Energy ◽  
Ann Model ◽  
Artificial Neural ◽  
Quenching And Tempering

This research involved a study of the heat treatment conditions effect on the mechanical properties of martensitic stainless steel type AISI 410. Heat treatment process was hardening of the metal by quenching at different temperature 900°C, 950°C, 1000°C, 1050°C and 1100°C, followed by double tempering at 200°C, 250°C, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C and 700°C, were evaluated and study of some mechanical properties such as hardness, impact energy and properties of tensile test such as yield and tensile strength is carried out. Multiple outputs Artificial Neural Network model was built with a Matlab package to predict the quenching and tempering temperatures. Also, linear and nonlinear regression analyses (using Data fit package) were used to estimate the mathematical relationship between quenching and tempering temperatures with hardness, impact energy, yield, and tensile strength. A comparison between experimental, regression analysis and ANN model show that the multiple outputs ANN model is more accurate and closer to the experimental results than the regression analysis results. 

The Application of Grinding of Ceramic Materials

2018 ◽  
Vol 919 ◽  
pp. 215-221
Author(s):  
Dana Stancekova ◽  
Jana Petrů ◽  
Jaroslava Svobodova ◽  
Izabela Miturska ◽  
Sarka Molotova
Keyword(s):  
Mechanical Properties ◽  
Surface Roughness ◽  
Production Process ◽  
Cutting Forces ◽  
High Hardness ◽  
Ceramic Materials ◽  
Cutting Conditions ◽  
Whole Process ◽  
Technical Ceramics ◽  
Roughness Evaluation

An application of hard engineering materials depends especially on their specific properties, included mechanical properties and their machinability. Technical ceramics belongs to such materials. Nowadays, due to its properties, it is a process of grinding that is applied in machining. Because the technical ceramics has high hardness and brittleness it is important to pay attention to the whole process of machining. In this case of the grinding, there is need to pay attention to the process from disc engagement to grind off the desired layer. The paper deals with an implementation of grinding of ceramic materials in context of determining of elements of cutting forces and the surface roughness evaluation. These are important aspects for determining the suitability of the cutting conditions and the possibility of their use in the production process.

scholarly journals Effect of Preheating Temperature on Microstructure and Properties of 42CrMo4/38MnVS6 Heterogeneous Laser Welded Joint

Metals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 870
Author(s):  
Jinlong Su ◽  
Xiaoming Qiu ◽  
Fei Xing ◽  
Ye Ruan
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Welded Joint ◽  
Lath Martensite ◽  
High Hardness ◽  
Absorption Capacity ◽  
New Era ◽  
Laser Absorption ◽  
Preheating Temperature ◽  
Heavy Truck

Laser-welded forged steel pistons can meet the needs of the new era of heavy truck engines. 42CrMo4 and 38MnVS6 are widely used as piston materials due to the good mechanical properties. This study investigates the influence of preheating on microstructure and mechanical properties of 42CrMo4/38MnVS6 laser welding joint. The experimental results show preheating increases the laser absorption capacity of the metal, which can lead to an increase in weld width. The microstructure of weld is the high-hardness and poor toughness twin martensite without preheating. As the temperature of preheating increases, the twin martensite in the weld begins to transform into lath martensite and regenerates ferrite and bainite. As the preheating temperature increases, the plane fracture toughness (K1C) of the weld increases and then decreases, reaching the highest value of 2322.94 MPa·mm−1/2 at 150 °C. Compared with no preheating conditions, the tensile strength of the welded joint after preheating is improved. The fracture mode of welded joints changes from brittle fracture to ductile fracture. When the preheating temperature is 100–200 °C, the tensile strength of the welded joint reaches 1018.1–1032.5 MPa; when the preheating temperature is 250 °C–300 °C, the tensile strength decreases.

scholarly journals The Influence of the Production Process on Mechanical Properties of Rubber Testing Samples

2014 ◽  
Vol 1025-1026 ◽  
pp. 37-41
Author(s):  
Adam Skrobak ◽  
Michal Stanek ◽  
David Manas ◽  
Martin Ovsik ◽  
Vojtech Senkerik ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Injection Molding ◽  
Production Process ◽  
Production Technology ◽  
Tear Strength ◽  
Rubber Compounds ◽  
Negative Effect

The article deals with the influence of production technology on mechanical properties of rubber testing samples. In practice, rubber testing samples are cut out from a compression molded sheet, also in case of testing of rubber compounds appointed for injection molding. However, the different way of the preparation of testing samples and the production itself may have a negative effect on the mechanical properties of the final product. Thus the article judges, to what extent the mechanical properties (tensile strength, extension, tear strength and microhardness) of testing samples from selected rubber materials are influenced by injection molding, and evaluates the possible divergence.

scholarly journals Effect of Different Variants of Heat Treatment on Mechanical Properties of the AlSi17CuNiMg Alloy

2016 ◽  
Vol 16 (2) ◽  
pp. 41-44 ◽  
Author(s):  
A. Jarco ◽  
J. Pezda
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Impact Strength ◽  
High Hardness ◽  
Dispersion Hardening ◽  
Initial State ◽  
Plastic Properties ◽  
Fourfold Increase ◽  
The Impact

Abstract Dispersion hardening, as the main heat treatment of silumins having additions of copper and magnesium, results in considerable increase of tensile strength and hardness, with simultaneous decrease of ductility of the alloy. In the paper is presented an attempt of introduction of heat treatment operation consisting in homogenizing treatment prior operation of the dispersion hardening, to minimize negative effects of the T6 heat treatment on plastic properties of hypereutectoidal AlSi17CuNiMg alloy. Tests of the mechanical properties were performed on a test pieces poured in standardized metal moulds. Parameters of different variants of the heat treatment, i.e. temperature and time of soaking for individual operations were selected basing on the ATD (Thermal Derivation Analysis) diagram and analysis of literature. The homogenizing treatment significantly improves ductility of the alloy, resulting in a threefold increase of the elongation and more than fourfold increase of the impact strength in comparison with initial state of the alloy. Moreover, the hardness and the tensile strength (Rm) of the alloy decrease considerably. On the other hand, combination of the homogenizing and dispersion hardening enables increase of elongation with about 40%, and increase of the impact strength with about 25%, comparing with these values after the T6 treatment, maintaining high hardness and slight increase of the tensile strength, comparing with the alloy after the dispersion hardening.

Sign in / Sign up

Export Citation Format

Share Document