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Laser Welding of TA15 Titanium Alloy and Inconel 718 Dissimilar Metals

An Qi, Wu Dongting, Liu Peng, Zou Yong

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 4

1267--1276

EN

This paper studied the effect of laser welding technology on dissimilar metal welding joints of TA15 titanium alloy and Inconel 718 nickel-based alloy. The research results indicate that the laser welding of TA15 titanium alloy and Inconel 718 nickel-based alloy directly was difficult to form well, which due to the intermetallic compounds caused the joint brittle. When the pure Cu foil was used as the filling layer, the quality of the welding joints can be improved effectively. The experimental results also indicate that there were brittle intermetallic-compounds in the laser welding seam, and the laser power had an important influence on the performance and mechanical properties of the dissimilar metal joint. The maximum average tensile strength of the welding joint of 2300 W was increased to 252.32 MPa. Scanning electron microscope(SEM) results show that the fracture morphology was river pattern, a typical morphological of cleavage fracture, and the mode was brittle fracture.

2

Structure and properties of alloys of the Mg-Al-Zn system

Cizek L., Greger M., Dobrzański L. A., Juricka I., Kocich R., Pawlica L., Tański T.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 32, nr 2

179-187

EN

Purpose: In the following paper there have been the structure and complex of mechanical properties of magnesium alloys presented which requires very often knowledge of elastic-plastic properties at elevated temperatures. These properties are connected with microstructure that is influenced by metallurgical and technological factors and conditions of exploitation. The influence of used method ECAP for superplasticity will be investigated. Design/methodology/approach: The tensile test in dependence on temperature of magnesium alloys was based on investigation of mechanical properties. The following results concern light and scanning microscopy for metallographic and fracture analyses of alloys after testing were used. Findings: Objective of this work consisted in determination of changes of elastic-plastic properties of magnesium alloy AZ91 as cast state and after heat treatment in dependence on temperature, including investigation of fracture characteristics. It was confirmed that during heating used alloy as cast state at chosen temperatures there occurs partial dissolution of minority phases. Homogenisation of microstructure is, however, accompanied by simultaneous forming of inter-granular non-integrities, which is unfavourable from the viewpoint of strength and plastic properties, especially at higher temperatures. Failure occurs practically at all temperatures basically by inter-crystalline splitting along the boundaries of original dendrites. At temperature testing near melting point of alloy the interdendrite areas melting were observed. After application ECAP the effect of superplasticity (200-400%) was occurred. Practical implications: The results may be utilized for a relation between plastic and strength properties of the investigated material in process of manufacturing and design of these materials. Originality/value: Complex evaluation of properties magnesium alloys at higher temperatures namely for explanation of fracture mechanism near the melting point. The possibility of supperplasticity effect of Mg-Al alloys was not presented yet.

3

Fatigue failure of micro-alloyed 23MnB4 steel

Rusz S., Cizek L., Filipec P., Pastrnak M.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 31, nr 2

356-363

EN

Purpose: In the following paper there have been the structure and fatigue properties of micro-alloyed 23MnB4 steel in initial state and after heat treatment evaluated. Design/methodology/approach: Fatigue test of micro-alloyed 23MnB4 steel was completed by metallographic and fracture analyses. For scope the methods of the light microscopy and SEM were used. Findings: Microstructure of examined alloy in initial state was characterized mostly by fine ferrite with pearlitic net and in state after heat treatment was formed by martensite or partly by bainite and after tempering was formed by tempered martensite. Objective of this work consisted in determination of fatigue characteristics of micro-alloyed 23MnB4 steel, including fracture analyze. Results of fatigue testing at various stress levels for the samples in initial state and after the heat treatment have confirmed that obtained values of cycles to rupture were at least 585 000 cycles. Change of fatigue properties in dependence on heat treatment of the used steel. Research limitations/implications: For define fracture area a samples must be provide with notch. The experiment was limited by occurrence a void in cast alloys. Practical implications: The results may be utilized for application of the investigated material in process of manufacturing. Originality/value: These results contribute to explanation of fracture mechanism of micro-alloyed 23MnB4 steel.

4

Fracture analysis of selected magnesium alloys after different testing methods

Čižek L., Greger M., Dobrzański L. A., Kocich R., Tański T., Praźmowski M.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 24, nr 2

131-134

EN

Purpose: of this paper is to extend a complex evaluation of magnesium alloys which requires very often knowledge mechanical properties. These properties are connected with microstructure that is influenced by metallurgical and technological factors and conditions of exploitation. Very important information for design and exploitation of these alloys is knowledge of fracture characteristics. Design/methodology/approach: Testing methods used magnesium alloys were based on tensile test and torsion test. The methods of the light microscopy and SEM for metallographic and fracture analyses of alloys after testing were used. Findings: Objective of this work consisted in determination of changes of mechanical properties and fracture characteristics of magnesium alloy in dependence on testing methods. Mg-Al alloy with graduate aluminium content as cast state and after heat treatment was used. It was confirmed that during heating at chosen temperatures there occurs partial dissolution of minority phases. Research limitations/implications: According to the alloys characteristic, the applied cooling rate and alloy additions seems to be a good compromise for mechanical properties and microstructures, nevertheless further tests should be carried out in order to examine different cooling rates and parameters of solution treatment process and aging process. Practical implications: The results may be utilized for a relation between plastic and strength properties of the investigated material in process of research and manufacturing. Originality/value: These results contribute to complex evaluation of properties magnesium alloys namely for explanation of fracture mechanism in changing condition of testing and exploitation. The results of this paper are determined for research workers deal by development new exploitations of magnesium alloys.

5

Mechanical properties of magnesium alloy AZ91 at elevated temperatures

Čížek L., Greger M., Dobrzański L. A., Juřička I., Kocich R., Pawlica L., Tański T.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 18, nr 1-2

203--206

EN

Purpose: Purpose of this article is to extend a complex evaluation of magnesium alloys which requires very often knowledge of elastic-plastic properties at elevated temperatures. These properties are connected with microstructure that is influenced by metallurgical and technological factors and conditions of exploitation. Design/methodology/approach: Methodology Testing of magnesium alloys was based on tensile test in dependence on temperature. The methods of the light microscopy and SEM for metallographic and fracture analyses of alloys after testing were used. Findings: Objective of this work consisted in determination of changes of elastic-plastic properties of magnesium alloy AZ91 in dependence on temperature, including investigation of fracture characteristics. It was confirmed that during heating at chosen temperatures there occurs partial dissolution of minority phases. Homogenisation of microstructure is, however, accompanied by simultaneous forming of inter-granular non-integrities, which is unfavourable from the viewpoint of strength and plastic properties, especially at higher temperatures. Failure occurs practically at all temperatures basically by inter-crystalline splitting along the boundaries of original dendrites. At temperature testing near melting point of alloy the interdendrite areas melting were observed. Research limitations/implications: The experiment was limited by occurrence a void in cast alloys. Practical implications: The results may be utilized for a relation between plastic and strength properties of the investigated material in process of manufacturing. Originality/value: These results contribute to complex evaluation of properties magnesium alloys at higher temperatures namely for explanation of fracture mechanism near the melting point.

6

Evaluation of fatigue of micro-alloyed 23MnB4 steel

Rusz S., Cizek L., Filipec P.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 18, nr 1-2

223--226

EN

Purpose: Purpose of this article is to extend a complex evaluation of fatigue properties of micro-alloyed 23MnB4 steel in initial state and after heat treatment. Design/methodology/approach: Testing of micro-alloyed 23MnB4 steel was based on fatigue test completed by metallographic and fracture analyses. The methods of the light microscopy and SEM were used. Findings: Objective of this work consisted in determination of fatigue characteristics of micro-alloyed 23MnB4 steel, including fracture analyze. Results of fatigue testing at various stress levels for the samples in initial state and after the heat treatment have confirmed that obtained values of cycles to rupture were at least 585 000 cycles. Change of fatigue properties in dependence on heat treatment of the used steel. Research limitations/implications: The experiment was limited by occurrence a void in cast alloys. Practical implications: The results may be utilized for application of the investigated material in process of manufacturing. Originality/value: These results contribute to explanation of fracture mechanism of micro-alloyed 23MnB4 steel.