Der Dauerbruch in perlitischem Gußeisen mit Lamellengraphit / Fatigue Fracture in Pearlitic Cast Iron with Lamellar Graphite

Grey cast iron is one of the most common engineering materials used to make castings which work in thermal cycling. Under thermal cycling conditions, heat resistance is an important operational property of grey cast iron, which depends to the greatest extent on its structure – size and shape of the graphite inclusions, as well as the metal matrix composition. In this paper, the heat resistance of unalloyed grey cast iron with lamellar and compact graphite distributed in perlitic and perlitic-ferritic metal matrices was determined. The tests were carried out at temperatures of 500 – 800 °C. The results of the studies showed an insignificant difference of perlitic and perlitic-ferritic grey cast iron with lamellar graphite heat resistance. The heat resistance of perlitic ferritic grey cast iron with compact graphite is 16 – 48 % higher than the heat resistance of perlitic ferritic grey cast iron with lamellar graphite. Thus, when the shape of the graphite inclusions changed from lamellar to compact, a significant increase in the heat resistance of unalloyed grey cast iron occurred.

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The influence of cryogenic processing on wear on the impact wear resistance of low carbon steel and lamellar graphite cast iron

Wear ◽

10.1016/j.wear.2011.01.041 ◽

2011 ◽

Vol 271 (9-10) ◽

pp. 1481-1489 ◽

Cited By ~ 14

Author(s):

T. Slatter ◽

R. Lewis ◽

A.H. Jones

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Carbon Steel ◽

Low Carbon Steel ◽

Impact Wear ◽

Low Carbon ◽

Graphite Cast Iron ◽

Lamellar Graphite ◽

Cryogenic Processing ◽

The Impact

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X-Ray Fractographic Study on Fatigue Fracture Surface of Ductile Cast Iron

Advances in X-ray Analysis ◽

10.1154/s0376030800015834 ◽

1993 ◽

Vol 37 ◽

pp. 327-334

Author(s):

Akira Suzuki ◽

Yoichi Kishi ◽

Zenjiro Yajima ◽

Yukio Hirose

Keyword(s):

Cast Iron ◽

Fracture Surface ◽

Fatigue Fracture ◽

Retained Austenite ◽

Volume Fraction ◽

Compact Tension ◽

Fatigue Tests ◽

Ductile Cast Iron ◽

Fatigue Fracture Surface ◽

X Ray

Austempered ductile cast iron (ADI) has composite microstructures, which are martensite/retained austenite structures. ADI has very large toughness compared to other ductile cast irons. After fracture, the retained austenite near the fracture surface will be transformed to martensite. In the present study, X-ray fractography is applied to fatigue fracture surface of ADI. The fatigue tests were carried out on compact tension (CT) specimens. The volume fraction of retained austenite was quantitatively measured on and beneath fatigue fracture surfaces. The plastic strain on the fracture surface was estimated from measuring the line broadening of X-ray diffraction profiles. The depth of the plastic zone left on fracture surface was evaluated from the distributions of the volume fraction of retained austenite. The results are discussed on the basis of fracture mechanics.

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Fatigue Characteristic of Spheroidal Vanadium Carbides Cast Iron

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.457.279 ◽

2010 ◽

Vol 457 ◽

pp. 279-284 ◽

Cited By ~ 2

Author(s):

Masahito Tanaka ◽

Kazumichi Shimizu ◽

Daijiro Ito ◽

Toru Noguchi

Keyword(s):

Cast Iron ◽

Fracture Surface ◽

Fatigue Fracture ◽

Vanadium Carbide ◽

High Hardness ◽

Fatigue Characteristic ◽

Matrix Microstructure ◽

Secondary Cracks ◽

The Matrix ◽

Vanadium Carbides

The purpose of this study is to investigate the fatigue characteristic and fatigue fracture mechanism of the high V-Cr-Ni spheroidal carbide cast iron (SCI-VCrNi) with spheroidal vanadium carbide (VC) dispersed within austenitic stainless matrix microstructure. The SCI-VCrNi that has high hardness was developed by 10mass%V adding to 18-8 stainless steel with spheroidal VC is distributed in the matrix. Firstly from the plane bending, the fatigue limit σw has been found to the 358MPa of SCI-VCrNi. Secondly, fracture surface observations were performed to clarify the fatigue mechanism of SCI-VCrNi. The fracture surface of SCI-VCrNi was so rough that the beach mark could not be observed. So, SEM was employed to observe, the fatigue fracture surface which showed a particular fatigue pattern. Also, many fracture cracks of VC were observed. In addition, the secondary cracks are shown at the interface between VC and the matrix. It can be suggested that the bondability between VC and the matrix is strong, and therefore, the propagation of cracks was delayed by the breakage of VC.

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On the Mechanics of Grey Cast Iron Under Pure Bending

Journal of Engineering Materials and Technology ◽

10.1115/1.3225851 ◽

1986 ◽

Vol 108 (2) ◽

pp. 141-146 ◽

Cited By ~ 7

Author(s):

G. S. A. Shawki ◽

S. A. R. Naga

Keyword(s):

Cast Iron ◽

Bending Strength ◽

Neutral Axis ◽

Grey Cast Iron ◽

Stress And Strain ◽

Pure Bending ◽

Rectangular Section ◽

Bending Strain ◽

Grey Cast ◽

Lamellar Graphite

This paper presents the results of experiments conducted on lamellar graphite grey cast iron of rectangular section subjected to pure bending. Strain measurements confirm the traditional speculation that plane sections remain plane under strain. Owing to the nonlinear relationship between stress and strain, however, the neutral axis of a loaded specimen is shown to shift away from the centroidal axis. This shift is evidently amplified with increased loading. A computer program is herein specially devised for calculating the shift in neutral axis through satisfaction of the conditions of equilibrium together with checking for possible crack initiation at the extension side. While the simple flexural formula holds very nearly true for the compression side, it fails, however, to predict stresses on the extension side, the situation being further aggravated by higher bending moments. The apparent high bending strength of grey cast iron is fully accounted for.

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