scholarly journals Analysis of the influence of the hydrostatic ball burnishing pressure in the surface hardness and roughness of medium carbon steels

Author(s):  
P Fernández-Lucio ◽  
H González-Barrio ◽  
G Gómez-Escudero ◽  
O Pereira ◽  
L N López de Lacalle ◽  
...  
2005 ◽  
Vol 297-300 ◽  
pp. 1126-1132 ◽  
Author(s):  
Cong Ling Zhou ◽  
Shinichi Nishida ◽  
Nobusuke Hattori ◽  
Wen Xian Sun

This study was focused on the effects of pre-strain on the torsional fatigue properties of three kinds of medium carbon steels, including the fatigue strength, surface hardness, microstructure, and the crack initiation and propagation behaviors. The effect of pre-strain on the non-propagating cracks was also discussed. The main results obtained in this test are as follows: 1) the fatigue limits increase with the increasing of tensile pre-strain ratio for all kinds of the test materials; 2) under certain stress amplitude, with the increasing of tensile pre-strain ratio, the fatigue crack initiates a little earlier and propagates faster; 3) the length of non-propagating crack decreases with the increasing of tensile pre-strain ratio.


Author(s):  
Ramli ◽  
Chung-Chun Wu

Dog conch shell powder (DCSP) and coconut shell powder (CSP) are used as the calcium carbonate source (energizer) and carbon source, respectively, in the pack carburizing of SCM 420 low carbon steel. The surface hardness of the carburized specimens is investigated for various CSP:DCSP ratios and carburizing temperatures. It is found that a significant improvement in the hardness level is obtained for a DCSP concentration of 40% and a carburizing temperature of 950[Formula: see text]C. It is additionally shown that while DCSP can be used as an energizer in the carburizing process, it cannot be used as an activated carbon source. Finally, it is shown that the surface hardness of the carburized specimens can be significantly improved through a further quenching operation in water. Overall, the results presented in this study confirm the potential for utilizing natural resources such as DCSP and CSP for the pack carburizing of low-to-medium carbon steels.


Author(s):  
F. A. Khalid ◽  
D. V. Edmonds

The austenite/pearlite growth interface in a model alloy steel (Fe-1 lMn-0.8C nominal wt%) is being investigated. In this particular alloy pearlite nodules can be grown isothermally in austenite that remains stable at room temperature, thus facilitating examination of the transformation interfaces. This study presents preliminary results of thin foil TEM of the austenite/pearlite interface, as part of a programme of aimed at studying alloy carbide precipitation reactions at this interface which can result in significant strengthening of microalloyed low- and medium- carbon steels L Similar studies of interface structure, made on a partially decomposed high- Mn austenitic alloy, have been reported recently.The experimental alloys were made as 50 g argon arc melts using high purity materials and homogenised. Samples were hot- rolled, swaged and machined to 3mm diameter rod, solution treated at 1300 °C for 1 hr and WQ. Specimens were then solutionised between 1250 °C and 1000 °C and isothermally transformed between 610 °C and 550 °C for 10-18 hr and WQ.


Alloy Digest ◽  
1996 ◽  
Vol 45 (1) ◽  

Abstract INCO WELD C Electrode is a stainless-alloy electrode especially designed for shielded-metal-arc welding of a broad range of materials, including many difficult-to-weld compositions. It can be used in stainless steels, mild and medium-carbon steels,and spring steels. This datasheet provides information on composition, hardness, and tensile properties. It also includes information on joining. Filing Code: SS-632. Producer or source: Inco Alloys International Inc.


Author(s):  
A. S. Atamashkin ◽  
E. Yu. Priymak ◽  
N. V. Firsova

The paper presents an analysis of the mechanical behavior of friction samples of welded joints from steels 30G2 (36 Mn 5) and 40 KhN (40Ni Cr 6), made by rotary friction welding (RFW). The influence of various temperature conditions of postweld tempering on the mechanical properties and deformation behavior during uniaxial tensile testing is analyzed. Vulnerabilities where crack nucleation and propagation occurred in specimens with a welded joint were identified. It was found that with this combination of steels, postweld tempering of the welded joint contributes to a decrease in the integral strength characteristics under conditions of static tension along with a significant decrease in the relative longitudinal deformation of the tested samples.


Metals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 978 ◽  
Author(s):  
Pengfei Wang ◽  
Zhaodong Li ◽  
Guobiao Lin ◽  
Shitong Zhou ◽  
Caifu Yang ◽  
...  

Steels used for high-speed train wheels require a combination of high strength, toughness, and wear resistance. In 0.54% C-0.9% Si wheel steel, the addition of 0.075 or 0.12 wt % V can refine grains and increase the ferrite content and toughness, although the influence on the microstructure and toughness is complex and poorly understood. We investigated the effect of 0.03, 0.12, and 0.23 wt % V on the microstructure and mechanical properties of medium-carbon steels (0.54% C-0.9% Si) for train wheels. As the V content increased, the precipitation strengthening increased, whereas the grain refinement initially increased, and then it remained unchanged. The increase in strength and hardness was mainly due to V(C,N) precipitation strengthening. Increasing the V content to 0.12 wt % refined the austenite grain size and pearlite block size, and increased the density of high-angle ferrite boundaries and ferrite volume fraction. The grain refinement improved the impact toughness. However, the impact toughness then reduced as the V content was increased to 0.23 wt %, because grain refinement did not further increase, whereas precipitation strengthening and ferrite hardening occurred.


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