Influence of inorganic coating on protection from tufftriding (1st report, on the mechanical properties and fatigue strength of anti-tufftrided steel)

The ultrasonic impact treatment (UIT) is relatively new and promising process for fatigue life improvement of welded elements and structures. In most industrial applications this process is known as ultrasonic peening (UP). The beneficial effect of UIT/UP is achieved mainly by relieving of harmful tensile residual stresses and introducing of compressive residual stresses into surface layers of a material, decreasing of stress concentration in weld toe zones and enhancement of mechanical properties of the surface layers of the material. The UP technique is based on the combined effect of high frequency impacts of special strikers and ultrasonic oscillations in treated material. Fatigue testing of welded specimens showed that UP is the most efficient improvement treatment as compared with traditional techniques such as grinding, TIG-dressing, heat treatment, hammer peening and application of LTT electrodes. The developed computerized complex for UP was successfully applied for increasing the fatigue life and corrosion resistance of welded elements, elimination of distortions caused by welding and other technological processes, residual stress relieving, increasing of the hardness of the surface of materials. The UP could be effectively applied for fatigue life improvement during manufacturing, rehabilitation and repair of welded elements and structures. The areas/industries where the UP process was applied successfully include: Shipbuilding, Railway and Highway Bridges, Construction Equipment, Mining, Automotive, Aerospace. The results of fatigue testing of welded elements in as-welded condition and after application of UP are considered in this paper. It is shown that UP is the most effective and economic technique for increasing of fatigue strength of welded elements in materials of different strength. These results also show a strong tendency of increasing of fatigue strength of welded elements after application of UP with the increase in mechanical properties of the material used.

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The Relation between Forming Pressure for the Phenolic Resin Laminates and Rotating Bending Fatigue Strength, and a Few Other Mechanical Properties

journal of the Japan Society for Testing Materials ◽

10.2472/jsms1952.11.504 ◽

1962 ◽

Vol 11 (107) ◽

pp. 504-509

Author(s):

Toshinori KURODA ◽

Hajime TANIGUCHI

Keyword(s):

Mechanical Properties ◽

Fatigue Strength ◽

Phenolic Resin ◽

Bending Fatigue ◽

Rotating Bending Fatigue ◽

Rotating Bending ◽

Bending Fatigue Strength

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Effect of enhanced weld cooling on the mechanical properties of a structural steel with a yield strength of 700 MPa

SN Applied Sciences ◽

10.1007/s42452-020-03695-x ◽

2020 ◽

Vol 2 (11) ◽

Author(s):

Juhani Laitila ◽

Lassi Keränen ◽

Jari Larkiola

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Fatigue Strength ◽

Impact Toughness ◽

Yield Strength ◽

Uniform Elongation ◽

High Strength ◽

Low Alloy Steel ◽

External Cooling ◽

Welding Processes

AbstractIn this study, we present the effect of enhanced cooling on the mechanical properties of a high-strength low-alloy steel (having a yield strength of 700 MPa) following a single-pass weld process. The properties evaluated in this study include uniform elongation, impact toughness, yield, tensile and fatigue strengths alongside the cooling time of the weld. With the steel used in this study, the enhanced cooling resulted in a weld joint characterized with excellent cross-weld uniform elongation, yield and fatigue strength. The intensified cooling reduced the time it takes for the weld to reach 100 °C by around 190 s. Not only the fusion line of the weld was less pronounced, but also the grain size of the CGHAZ was greatly refined as a result of the enhanced cooling. The results indicate that combining external cooling to the welding processes can be beneficial for the studied high-strength steel.

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Mechanical Properties and Low Cycle Fatigue Strength at 4 and 300 K of Welded Alloy A286

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.73.14_1770 ◽

1987 ◽

Vol 73 (14) ◽

pp. 1770-1777 ◽

Cited By ~ 2

Author(s):

Keijiro HIRAGA ◽

Toshio OGATA ◽

Kotobu NAGAI ◽

Tetsumi URI ◽

Keisuke ISHIKAWA ◽

...

Keyword(s):

Mechanical Properties ◽

Fatigue Strength ◽

Low Cycle Fatigue ◽

Cycle Fatigue

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Fatigue strength of bellows and the effects of manufacturing techniques on the mechanical properties of 08Kh18N10T steel

Strength of Materials ◽

10.1007/bf01532500 ◽

1977 ◽

Vol 9 (3) ◽

pp. 366-368

Author(s):

I. V. Petrushin ◽

V. M. Sidorov ◽

N. G. Sinitsyn ◽

O. I. Fedorov ◽

A. V. Tsvilev

Keyword(s):

Mechanical Properties ◽

Fatigue Strength ◽

08Kh18n10t Steel ◽

Manufacturing Techniques

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Relationships among the Microstructure, Mechanical Properties, and Fatigue Behavior in Thin Ti6Al4V

Advances in Materials Science and Engineering ◽

10.1155/2016/7278267 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 13

Author(s):

Y. Fan ◽

W. Tian ◽

Y. Guo ◽

Z. Sun ◽

J. Xu

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Fatigue Strength ◽

Laser Welding ◽

Fracture Strength ◽

Fatigue Behavior ◽

Fatigue Properties ◽

Proof Stress ◽

Martensite Microstructure

The microstructures of Ti6Al4V are complex and strongly affect its mechanical properties and fatigue behavior. This paper investigates the role of microstructure on mechanical and fatigue properties of thin-section Ti6Al4V sheets, with the aim of reviewing the effects of microstructure on fatigue properties where suboptimal microstructures might result following heat treatment of assemblies that may not be suited to further annealing, for example, following laser welding. Samples of Ti6Al4V sheet were subjected to a range of heat treatments, including annealing and water quenching from temperatures ranging from 650°C to 1050°C. Micrographs of these samples were inspected for microstructure, and hardness, 0.2% proof stress, elongation, and fracture strength were measured and attributed back to microstructure. Fractography was used to support the findings from microstructure and mechanical analyses. The strength ranking from high to low for the microstructures of thin Ti6Al4V sheets observed in this study is as follows: acicularα′martensite, Widmanstätten, bimodal, and equiaxed microstructure. The fatigue strength ranking from high to low is as follows: equiaxed, bimodal, Widmanstätten, and acicularα′martensite microstructure.

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Mechanical Properties and Fatigue Strength of Extruded Cobalt-Containing Magnetic Magnesium Alloys

The Minerals, Metals & Materials Series - Magnesium Technology 2017 ◽

10.1007/978-3-319-52392-7_74 ◽

2017 ◽

pp. 537-542 ◽

Cited By ~ 1

Author(s):

Christian Demminger ◽

Christian Klose

Keyword(s):

Mechanical Properties ◽

Fatigue Strength ◽

Magnesium Alloys

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A Case Study of Gas Leakage and Assessment of Mechanical Properties With Welding Variables in Fillet Weldment of Small Diameter Pipe

Volume 3: Materials and Joining; Pipeline Automation and Measurement; Risk and Reliability, Parts A and B ◽

10.1115/ipc2006-10102 ◽

2006 ◽

Author(s):

Jong-Hyun Baek ◽

Woo-Sik Kim

Keyword(s):

Mechanical Properties ◽

Fatigue Strength ◽

Natural Gas ◽

Weld Zone ◽

Branch Pipe ◽

Small Diameter ◽

Welding Process ◽

Pipe Diameter ◽

Pipe Material ◽

Gas Leakage

A branched pipe joint has been employed to execute the pressure control, condition check, purgation, and distribution of the gas in the natural gas facilities. Installation of branch pipes is generally done through the welding work, and as a welding process, the weldolet and the sockolet are used. During the maintenance working of in-service natural gas pipeline, there was gas leakage in sockolet weldment. The causes of incident were investigated with various tests. We found the wrong pipe material, the weld defect and the non-destructive test limitation of fillet weldment as the reasons of gas leakage. As the follow-up measures, it was done to assess the soundness depending upon the configuration of the weld zone, a change in the welding process and a change in the pipe diameter by assessing the mechanical properties of the sockolet weld zone and further to assess comparatively the mechanical performance of the sockolet weld zone and that of the weldolet weld zone. In the sockolet weld, the tensile strength showed no difference and the fatigue strength showed a difference depending upon a change in the welding process. In the case that the leg length of the weld zone was made lengthwise in the direction of the branch pipe, the SMAW welding work compare with the GTAW, the sectional area of the weld zone was more increased, and the pipe diameter was more increased, the fatigue strength was increased.

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