Mechanism of Internal Surface Crack Formation of Seamless Modified 9Cr-1Mo Steel Tube Rolled by Mandrel Mill and Its Application

Experiments were conducted involving the upsetting of solid cylinders and rings of annealed SAE 1040 steel at room temperature for various end conditions. Measurements were made on the displacement distributions at the tool-workpiece interface, and on the development of barreling and strain variations at the free surface. Crack formation at the free surface was observed. The relationship between friction at the interface, deformation characteristics, and fracturing is discussed, and a tentative analysis is given for formulating the strains at the free surface, based on the experimental measurements for upsetting solid cylinders.

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Study on the Mechanism of Optical Glass Sub-Surface Crack Formation in Single Abrasive Grinding

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.523-524.1 ◽

2012 ◽

Vol 523-524 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Jiang Chen ◽

Fei Hu Zhang ◽

Hang Zhao ◽

Zhang Yong ◽

Li Fei Liu

Keyword(s):

Surface Crack ◽

Crack Formation ◽

Optical Glass

Removed due to plagiarism

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Heat-flow-based analysis of surface crack formation during the start-up of the direct chill casting process: Part I. development of the inverse heat-transfer model

Metallurgical and Materials Transactions B ◽

10.1007/bf02915083 ◽

1996 ◽

Vol 27 (1) ◽

pp. 119-127 ◽

Cited By ~ 9

Author(s):

J. B. Wiskel ◽

S. L. Cockcroft

Keyword(s):

Heat Transfer ◽

Heat Flow ◽

Surface Crack ◽

Crack Formation ◽

Casting Process ◽

Direct Chill ◽

Transfer Model ◽

Inverse Heat Transfer ◽

Start Up ◽

Direct Chill Casting Process

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Surface-crack formation in the manufacture of microalloyed steel pipe

Steel in Translation ◽

10.3103/s0967091216090035 ◽

2016 ◽

Vol 46 (9) ◽

pp. 665-670 ◽

Cited By ~ 5

Author(s):

N. G. Kolbasnikov ◽

V. V. Mishin ◽

I. A. Shishov ◽

M. A. Matveev ◽

A. M. Korchagin

Keyword(s):

Surface Crack ◽

Crack Formation ◽

Microalloyed Steel ◽

Steel Pipe

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Combined Peridynamics and Discrete Multiphysics to Study the Effects of Air Voids and Freeze-Thaw on the Mechanical Properties of Asphalt

Materials ◽

10.3390/ma14071579 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1579

Author(s):

Danilo Sanfilippo ◽

Bahman Ghiassi ◽

Alessio Alexiadis ◽

Alvaro Garcia Hernandez

Keyword(s):

Mechanical Properties ◽

Low Temperatures ◽

Crack Formation ◽

Compressive Load ◽

Internal Surface ◽

Operating Conditions ◽

Computational Tool ◽

Air Voids ◽

The Third ◽

Repulsive Forces

This paper demonstrates the use of peridynamics and discrete multiphysics to assess micro crack formation and propagation in asphalt at low temperatures and under freezing conditions. Three scenarios are investigated: (a) asphalt without air voids under compressive load, (b) asphalt with air voids and (c) voids filled with freezing water. The first two are computed with Peridynamics, the third with peridynamics combined with discrete multiphysics. The results show that the presence of voids changes the way cracks propagate in the material. In asphalt without voids, cracks tend to propagate at the interface between the mastic and the aggregate. In the presence of voids, they ‘jump’ from one void to the closest void. Water expansion is modelled by coupling Peridynamics with repulsive forces in the context of Discrete Multiphysics. Freezing water expands against the voids’ internal surface, building tension in the material. A network of cracks forms in the asphalt, weakening its mechanical properties. The proposed methodology provides a computational tool for generating samples of ‘digital asphalt’ that can be tested to assess the asphalt properties under different operating conditions.

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