Wyniki wyszukiwania - BazTech

1

The influence of quenching temperature on distortions during the individual quenching method

Wołowiec-Korecka E., Stachurski W., Zgórniak P., Korecki M., Brewka A., Byczkowska P.

Archives of Materials Science and Engineering

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2020

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Vol. 105, nr 2

80--85

EN

Purpose: In this paper, the impact of hardening temperature on the quenching distortions which occur during low-pressure carburizing with gas quenching - using the individual quenching method - was analysed. Design/methodology/approach: The reference elements were subjected to carburizing at 980°C, followed by gas quenching at temperatures of 860°C, 920°C and 980°C. The geometrical measurements of the elements were made before and after the chemical treatment and the size of the quenching distortions of their geometrical parameters was determined. Findings: It was demonstrated that a high temperature of quenching has an unfavourable effect on changes in cylindricity and roundness parameters but, at the same time, reduces the size of distortion of outer parameters. Low temperature quenching reduces quenching distortions of cylindricity and roundness parameters while increasing the distortion of outer dimensions. Research limitations/implications: Based on the research and analysis carried out in this work, it was found that the use of lower quenching temperature is justified in economic and quality terms. Practical implications: In the case of the aviation or automotive industry, very high quality of manufactured elements along with a simultaneous reduction of their production costs is extremely important. Maintaining the dimensions of the elements during heat treatment is extremely difficult. The tests allowed to determine the optimal hardening temperature, which brings with it acceptable deformations. Since it is easier to “repair” the outer geometrical dimensions (diameter, thickness), it seems that quenching from lower temperatures is a more favourable process. Originality/value: The conducted tests allowed to determine the most favourable conditions for hardening elements from the automotive industry, taking into account the occurring deformations and their subsequent processing

2

Devices for modern vacuum heat treatment

Korecki M., Brewka A., Wołowiec-Korecka E.

Archives of Materials Science and Engineering

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2019

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Vol. 95, nr 2

77--85

EN

Purpose: A review regarding the devices for vacuum heat treatment is presented. Design/methodology/approach: Devices for modern heat treatment has been reviewed. The devices has been classified regarding the heat treatment (quenching, carburizing, nitriding, tempering and annealing). The possible application, materials and parts for heat treatment as well as parameters of the devices has been analysed. Findings: There is a wide range of modern vacuum heat treatment devices. All currently used heat and thermo-chemical treatments may be proceed in vacuum equipment. It is also in many cases preferable to use vacuum- because of economic reasons, better metallurgical results or environmental friendliness. Also software simulators which facilitates the planning of heat treatment are available with the equipment. Practical implications: Because of the industry expectations regarding efficiency, quality, economy and safety, vacuum equipment becoming the subject of wider and wider attention. In particular, aerospace and automotive industries pay a lot of attention to these aspects. The basic task of vacuum devices is fast, effective, environmentally friendly production of high quality machine parts. Originality/value: The synthetic presentation of modern devices for vacuum heat treatment was presented, in particular furnaces for quenching, carburizing, nitriding, tempering and annealing. The products characteristic and applications has been presented. Also equipment for some advanced vacuum applications has been presented. Modern software which complements the devices in terms of designing heat treatment processes has been described.

3

Study on homogeneity and repeatability of single-piece flow carburizing system

Madej A., Brewka A., Wołowiec-Korecka E.

Journal of Achievements in Materials and Manufacturing Engineering

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2017

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Vol. 84, nr 2

68--75

EN

Purpose: The purpose of this paper was to determine the homogeneity and replicability of carburized layers obtained by a continuous single-piece flow method. Design/methodology/approach: A series of 100 gears was carburized under low pressure atmosphere using the single-piece flow method. The microstructures of the obtained carbon layers were investigated. Hardness penetration pattern and carbon concentration profiles were tested. Findings: The findings have shown the validity/correctness of the microstructures of the carburized layers obtained by the single-piece flow method. It has been proved that the carbon layer in every gear is uniform, what confirms that each element is affected by the same process conditions and the gears in the whole series can be precisely reproduced. Research limitations/implications: The short-pulse low-pressure carburizing technology needs further investigation to understand its all mechanisms fully. Practical implications: The single-piece flow method provides the uniform and reproducible carburized layers with the precision magnitude exceeding the abilities of currently used thermo-chemical furnaces. When applying the method it is possible to obtain a uniform carburized case in every single gear from the whole series of elements subjected to the process. Optimized configuration of process parameters and carbon-carrying mixture allows to meet the high expectations of a modern and future industry, what is most crucial in exploiting carburized steel gears. Originality/value: The applicability of the LPC single-piece flow method to a demanding mass production has been verified. The statistical validity of research results of the whole manufactured series of gears is being performed for the first time.

4

Low pressure carburizing in a large-chamber device for high-performance and precision thermal treatment of parts of mechanical gear

Wołowiec-Korecka E., Korecki M., Klimek L., Kula P., Brewka A., Buczek M.

Advances in Science and Technology. Research Journal

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2017

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Vol. 11, no 1

253--258

EN

This paper presents the findings of research of a short-pulse low pressure carburizing technology developed for a new large-chamber furnace for high-performance and precision thermal treatment of parts of mechanical gear. Sections of the article discuss the novel constructions of the device in which parts being carburized flow in a stream, as well as the low-pressure carburizing experiment. The method has been found to yield uniform, even and repeatable carburized layers on typical gear used in automotive industry.

5

System of single-piece flow case hardening for high volume production

Wołowiec-Korecka E., Korecki M., Stachurski W., Zgórniak P., Sawicki J., Brewka A., Sut M., Bazel M.

Archives of Materials Science and Engineering

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2016

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Vol. 79, nr 1

37--44

EN

Purpose: Purpose of this paper is development of single-piece flow system to precision thermal treatment of parts of mechanical gear using a short-pulse low-pressure carburising technology (developed for a new large-chamber furnace). Design/methodology/approach: Sections of the article discuss the novel constructions of the device in which parts being carburised flow in a stream, as well as the low-pressure carburising experiment. Findings: The method has been found proper carburised layers on typical gear used in automotive industry. Research limitations/implications: The short-pulse low-pressure carburising technology needs further investigation to fully understand its all mechanisms. Practical implications: The device resulting from the experiment can be a fully robotised part of a production line which can be included in a system of automatic control of a production process. Originality/value: The device resulting from the experiment is only known solution on the world.