TITLE

INCREASING THE WEAR RESISTANCE OF TOOL STEELS BY CRYOGENIC TREATMENT

AUTHOR(S)
Krot, P. V.; Bobir, S. V.; Zharkov, I. P.; Nefedieva, E. E.; Timofeev, G. V.
PUB. DATE
December 2013
SOURCE
Metallurgical Processes & Equipment;Dec2013, Vol. 34 Issue 4, p1
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Background: Cryogenic quenching or deep cryogenic treatment (DCT) is a known method of microstructure changing of alloyed and carbon steels, which greatly increases the wear resistance and hardness of cutting tools, but process parameters and heat treatment (HT) schedules are not definitely known for certain steel grades. Various issues are considered of using cryogenic temperatures (down to -196 °C) in the HT process of tool steels. The most appropriate approach is when DCT is included into the standard schedules of HT. Materials and/or methods: Deep cryogenic treatment was carried out of samples of several alloyed steels: P6M5 (cutters), 9XC (drills), IIIX15 (bearings) been passed standard heat treatment schedules. The whole time of samples holding in LN2 was 18 hours. A simplified testing method is used for comparative analysis of abrasive wear of tools based on drilling and sharpening machines. Micro hardness of tools was checked with standard device PMT-3. Steel microstructures were investigated with the optical microscope "Axiovert 200 M". Samples wear was estimated by analytical weighing machine VLA-200 with accuracy of 1 mg. Results: It was developed a cryogenic apparatus with digital control providing the programming of different modes of cooling and heating for deep cryogenic processing of tools. The main technical parameters of cryogenic apparatus are as following: LN2 consumption - 1L/1kg of tools; cooling/heating rate - 1-5 °C/min; amount of treated tools - 20 kg. Microstructure analysis showed a homogenization of grains and fine carbides precipitation. Comparative tests on abrasive wear and measurements of micro hardness were performed. Experiments showed the absence of correlation between wear resistance and micro hardness changes of different steels after DCT. Small changes in micro hardness (3.3 % of drills (9XC) and 24.5 % of bearings (IIIX15)) corresponded to significant improvement in wear resistance (65 and 59 % respectively). While greatly increased micro hardness (170 %) of cutters (R6M5) resulted in relatively small wear resistance (26 %). That is due to different ways of DCT influence: retained austenite transformation in 9XC, IIIX15 and fine carbides precipitation in R6M5 which has higher temperature of initial quenching and was subjected to high-temperature tempering, hence, contained small amounts of austenite before DCT. Conclusion. Directions are formulated for further research and development in order to choose appropriate HT schedules for different steels to increase the efficiency of DCT. Namely, interval between stages of quenching and DCT and time of holding in LN2 need to be determined.
ACCESSION #
94612624

 

Related Articles

  • TRATAMENTO CRIOGÊNICO E DE ALÍVIO DE TENSÕESEM UM AÇO AISI D2. da Silva Farina, Paula Fernanda; Farina, Alexandre Bellegard; Barbosa, Celso Antonio; Goldenstein, Helio // Tecnologia em Metalurgia, Materiais e Mineração;abr-jun2012, Vol. 9 Issue 2, p140 

    The effects of cryogenic treatments on an AISI D2 cold work tool steel using X-ray diffraction from syncronton radiation are studied. The aim of this work is to verify the effects of: i) time at cryogenic temperatures (3, 10 and 30 hours); ii) cryogenic temperatures (-80°C and -196°C);...

  • Influence of cobalt on the cryogenically treated W-Mo-V high speed steel. Gogte, Chandrashekhar Laxman; Peshwe, Dilip; Paretkar, Ravindra // AIP Conference Proceedings;6/8/2012, Vol. 1434 Issue 1, p1175 

    The presence of cobalt in high speed steels is of great interest to researchers and the users as well. Although cobalt bearing high speed steels are used on commercial basis, the influence of cobalt in cryogenically treated high speed steels is still under scanner. Some researchers have found...

  • Heat Treatment of Wear Resistant Steels for Mud Pumps. Nikiforova, S. M.; Filippov, M. A.; Zhilin, A. S. // Materials Science Forum;2016, Vol. 870, p181 

    Influence of different type heat treatment including high temperature quenching on wear resistance has been investigated. The two investigated steels are widely used in production of mud pumps. It was shown that Kh12MFL had better wear resistance in comparison with 150KhNML. Martensitic-carbide...

  • Corrosion Resistance of The Bearing Steel 67SiMnCr6-6-4 with Nanobainitic Structure. Skołek, E.; Dudzińska, K.; Kamiński, J.; Świątnicki, W.A. // Archives of Metallurgy & Materials;Mar2015, Vol. 60 Issue 1, p503 

    The paper describes a comparative study of the corrosion resistance of bearing steel 67SiMnCr6-6-4 after two kinds of nanostructuring treatments and two kinds of conventional quenching and tempering treatments. The nanostructuring treatment consisted of austempering with an isothermal quenching...

  • METALLURGICAL INVESTIGATION ON CRYOGENIC TREATED HSS TOOL. SENDOORAN, S.; RAJA, P. // International Journal of Engineering Science & Technology;2011, Vol. 3 Issue 5, p3992 

    In the field of mechanical engineering we are always looking for ways to improve the properties of material by doing so, we can improve the quality of the product we are making, reduced costs to both ourselves and our customer and possibly gain market share by offering a higher quality product....

  • Estimation of the Heat Stability of Hardened Cr-V Cast Irons. Koryagin, Yu. D.; Il'ichev, V. L. // Materials Science Forum;2016, Vol. 870, p558 

    The paper describes the structure, properties and heat stability of white cast irons containing 2.5 – 3.0 %C, 14 and 20 %Cr, 3 %V after the secondary hardness treatment (quenching from 1150 °C and double tempering at 560 °C). It is shown that after the secondary hardness treatment...

  • HOT -- AND COLD -- TECHNOLOGIES. Vernyi, Bruce // American Machinist;Nov2006, Vol. 150 Issue 11, p6 

    This article discusses various reports published within the issue, including one on the use of industrial lasers to provide heat treating and another on the cryogenic cooling process that uses liquid nitrogen to make cutting tools extremely cold.

  • Plastic strain induced damage evolution and martensitic transformation in ductile materials at cryogenic temperatures. Garion, C.; Skoczen, B. T. // AIP Conference Proceedings;2002, Vol. 614 Issue 1, p170 

    The Fe-Cr-Ni stainless steels are well known for their ductile behaviour at cryogenic temperatures. This implies development and evolution of plastic strain fields in the stainless steel components subjected to thermo-mechanical loads at low temperatures. The evolution of plastic strain fields...

  • Effect of Cryogenic Treatment on Properties of Tool Steels. Salabova, Petra; Prikner, Otakar; Sobotova, Jana; Jurci, Peter // Industrial Heating;Mar2013, Vol. 81 Issue 3, p41 

    The article presents a study which aims to identify the optimal cryogenic treatment (CT) that can aid to prolong the life cycle of cold-work tools. The study shows that there are no important advantages that would prolong the life cycle of tools by offering higher wear toughness and resistance....

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics