Influence of vacuum carburizing treatment on fatigue crack growth characteristic in DSG2
Journal Title: Frattura ed Integrità Strutturale - Year 2015, Vol 9, Issue 34
Abstract
The aim of this research is to clarify the influence of vacuum carburizing on the fatigue-crack progress characteristics of DSG2 steel. The test specimen tempering material (QT material) and vacuum carburizing material (VC material) has been used. The fatigue-crack progress was examined by subjecting the samples to four-point bending. The loading-capacity fixed experiment was done using a maximum load of Pmax = 4000–7000 N. The ΔK fixed experiment was done using a load of ΔK = 18–36 MPa√m. The crack progress speed of VC material fell, after the high crack progress speed was shown, and after it showed the minimum, it showed the tendency to go up again. This is considered to be what is depended on the compressive residual stress given to the carburizing layer. From this, it is thinkable that there is a crack progress depression effect in a carburizing layer. In VC material, a carburizing layer has a crack progress depression effect from a plunger-helix bottom to about 2.6 mm, and it turned out that it is larger than an effective carburizing layer. Moreover, in each ΔK, it was shown that depression effect revelation differs and the crack progress process accompanying it was able to be shown typically.
Authors and Affiliations
K. Nambu, N. Egami
Keywords
Related Articles
- EP ID EP133176
- DOI 10.3221/IGF-ESIS.34.29
- Views 53
- Downloads 0
Fast assessment of the critical principal stress direction for multiple separated multiaxial loadings
The critical plane calculation for multiaxial damage assessment is often a demanding task, particularly for large FEM models of real components. Anyway, in actual engineering requests, sometime, it is possible to...
Study of short cracks under biaxial fatigue
In this paper a methodology for evaluating crack initiation under biaxial conditions is presented. The methodology consists of evaluating the crack length automatically with digital processing of highmagnification...
Characterisation of crack tip fields under non-uniform fatigue loading
The paper analyses previously reported work, which uses digital image correlation to measure fatigue crack closure. As well as determining crack opening loads, the information on crack shape may be used to estimate the s...
Stress triaxiality influence on damaging micromechanisms in a pearlitic ductile cast iron
In the last decades, damaging micromechanisms in ductile cast irons (DCIs) have been widely investigated, considering both the matrix microstructure and the loading conditions influence. Considering the graphite...
Analysis of cracking of low-alloy copper stretched at elevated temperature
This paper presents both mechanical and structural aspects of micro-cracking of CuNi2Si copper alloy in CNCS grade revealed during the static tensile test in the temperature range between 20ºC and 800ºC. The...