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Effect of Ambient and Cryogenic Milling on the Microstructure and Properties of Tungsten Matrix Composites Fabricated by Activated Sintering

Year 2019, Volume: 40 Issue: 1, 204 - 212, 22.03.2019

Özge Balcı , Duygu Ağaoğulları , Mehmet Suat Somer , M. Lütfi Öveçoğlu

https://doi.org/10.17776/csj.385724

Abstract

Tungsten matrix composites reinforced with TiB2
and Y2O3 particles were fabricated by milling under
ambient/cryogenic conditions and Ni activated sintering. Powder blends
constituting the W - 1 wt. % Ni - 2 wt. % TiB2 - 1 wt. % Y2O3
composition were mechanically milled for 12 h under ambient condition or cryomilled
for 10 min or sequentially milled under ambient and cryogenic conditions.
Milling was carried out in a high-energy ball mill under ambient condition
whereas cryogenic milling was conducted in externally circulated liquid
nitrogen. Milled powders were compacted using a hydraulic press and the pellets
were sintered at 1400°C for 1 h under Ar / H2 gas flowing
conditions. The effects of different milling types on the microstructural and
mechanical properties of the sintered composites were investigated. After
sintering, in addition to dominant W phase, small amounts of WB and NiW phases
were detected in all sintered samples. The application of cryomilling after
milling at ambient condition provided the disappearance of the clustered TiB2
and Y2O3 particles in the sintered sample: They were
located at the grain boundaries of W1Ni matrix and homogeneously distributed
through the microstructure. Sequentially milled and sintered composite had the
highest relative density (95.77 %) and the highest microhardness (7.23 GPa)
values among the samples. Nano-indentation tests showed that there was an
improvement in the hardness and elastic modulus of W matrix phase, which
yielded the values of 8.9 and 373.7 GPa, respectively.

Keywords

Tungsten matrix composites Cryomilling Activated sintering TiB2 Y2O3

References

  • [1]. Lassner E., Schubert W.D., Tungsten: Properties, Chemistry, Technology of the Element, Alloys and Chemical Compounds, Kluwer Academic, New York, 1999.
  • [2]. Caldwell S.G., Tungsten heavy alloys, in: Lee P.W., Lacocca R. (Eds.), Powder Metal Technologies and Applications, ASM Handbook (v. 7), ASM International, Materials Park, Ohio, 1998, pp. 914–921.
  • [3]. Arshad K., Wang J., Yuan Y., Zhang Y., Zhou Z.-J. and Lu G.-H., Development of tungsten-based materials by different sintering techniques, Int. J. Refract. Met. Hard Mater., 50 (2015) 253–257.
  • [4]. Wei B., Wang Y., Zhao Y., Wang D., Song G., Fu Y. and Zhou Y., Effect of NbC content on microstructure and mechanical properties of W-NbC composites, Int. J. Refract. Met. Hard Mater., 70 (2018) 66–76.
  • [5]. Li Y., Zhang J., Luo G., Shen Q., and Zhang L., Densification and properties investigation of W-Cu composites prepared by electroless-plating and activated sintering, Int. J. Refract. Met. Hard Mater., 71 (2018) 255–261.
  • [6]. German R.M. and Munir Z.A., Enhanced low-temperature sintering of tungsten, Metall. Mater. Trans. A 7 (1976) 1873–1877.
  • [7]. Hayden H.W. and Brophy J.H., The activated sintering of tungsten with group VIII elements, J. Electrochem. Soc. 110 (1963) 805–810.
  • [8]. Song G.M., Wang Y.J. and Zhou Y., The mechanical and thermophysical properties of ZrC/W composites at elevated temperature, Mater. Sci. Eng. A-Struct. 334 (2002) 223–232.
  • [9]. Kim Y., Lee H.K., Kim E., Cheong D. and Hong S.H., Fabrication of high temperature oxides strengthened tungsten composites by spark plasma sintering process, Int. J. Refract. Met. Hard Mater. 27 (2009) 842–846.
  • [10]. Chen Y., Wu Y.C., Yu F.W. and Chen J.L., Microstructure and mechanical properties of tungsten composites co-strengthened by dispersed TiC and La2O3 particles, Int. J. Refract. Met. Hard Mater. 26 (2008) 525–529.
  • [11]. Liu W., Xue L. and Yan Y., Microstructure and mechanical properties of W-Cr-TiN composite by spark plasma sintering, Fusion Engineering and Design, 125 (2017) 503–509.
  • [12]. Ağaoğulları D., Balcı Ö., Gökçe H., Öveçoğlu M. L. and Duman I., Comparative investigations of the activated sintered W–1wt.% Ni composites reinforced with various oxide and boride particles, Int. J. Refract. Met. Hard Mater. 41 (2013) 577–584.
  • [13]. Li B., Sun Z., Hou G., Ding F., Hu P. and Yuan F., The effects of alumina reinforcement and nickel activated sintering on nanosized tungsten matrix, J.Alloy. Compd., 692 (2017) 420–426.
  • [14]. Genç A., Çoşkun S. and Öveçoğlu M.L., Microstructural characterizations of Ni activated sintered W-2 wt % TiC composites produced via mechanical alloying, J.Alloy. Compd. 497 (2010) 80–89.
  • [15]. Gökçe H., Balcı Ö., Ağaoğulları D., Demirkan Ö., Genç A., Öveçoğlu M.L. and Duman I., Characterization Investigations of W-Ni Matrix Composites Reinforced with TiB2 and La2O3, Acta Physica Polonica A, 123-2 (2013) 309–312.
  • [16]. Balcı Ö., Demirkan Ö. U., Ağaoğulları D., Gökçe H., Genç A., Öveçoğlu M. L. and Duman I., Effects of La2O3 Addition on the microstructure and properties of activated sintered W-Ni Compacts, Solid State Phenomen. 194 (2012) 217–221.
  • [17]. Munro R.G., Material properties of titanium diboride, J. Res. Natl. Inst. Stan. 105 (2000) 709-720.
  • [18]. Battabyal M., Schäublin R., Spätig P. and Baluc N., W–2wt. %Y2O3 composite: Microstructure and mechanical properties, Mat. Sci. Eng. A, 538, (2012) 53–57.
  • [19]. Genç A., Coşkun S. and Öveçoğlu M., Fabrication and properties of mechanically alloyed and Ni activated sintered W matrix composites reinforced with Y2O3 and TiB2 particles, Mater. Charact. 61-7 (2010) 740–748.
  • [20]. Çoşkun S. and Öveçoğlu M.L., Effects of Y2O3 additions on mechanically alloyed and sintered W-4 wt% SiC composites, Int. J. Refract. Met. Hard Mater. 29 (2011) 651–655.
  • [21]. Gupta V.K., Yoon D.H., Meyer H.M. and Luo J., Thin intergranular films and solidstate activated sintering in nickel-doped tungsten, Acta Mater. 55 (2007) 3131–3142.
  • [22]. Ağaoğulları D., Balcı Ö. and Öveçoğlu M. L., Effect of milling type on the microstructural and mechanical properties of W-Ni-ZrC-Y2O3 composites, Ceram. Int. 43-9 (2017) 7106–7114.
  • [23]. Back S.H., Lee G.H. and Kang S., Effect of cryomilling on particle size and microstrain in a WC-Co alloy, Mater. Trans. 46 (1) (2005) 105–110.
  • [24]. Veleva L., Oksiuta Z., Vogt U. and Baluc N. Sintering and characterization of W–Y and W–Y2O3 materials. Fusion Eng. Des. 84 (2009) 1920–1924.
  • [25]. Suryanarayana C., Mechanical alloying and milling, Prog. Mater. Sci. 46 (2001) 1–184.
  • [26]. Oliver W.C. and Pharr G.M., An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments, Journal of Materials Research 7-6 (1992) 1564–1583.

Normal ve Kriyojenik Şartlarda Öğütmenin Aktive Edilmiş Sinterleme Süreçleri ile Geliştirilen Tungsten Esaslı Kompozitlerin Mikroyapı ve Özellikleri Üzerindeki Etkisi

Year 2019, Volume: 40 Issue: 1, 204 - 212, 22.03.2019

Özge Balcı , Duygu Ağaoğulları , Mehmet Suat Somer , M. Lütfi Öveçoğlu

https://doi.org/10.17776/csj.385724

Abstract

Bu çalışmada, Ni ile aktive edilerek sinterlenen tungsten esaslı
matrisin TiB2 ve Y2O3 partikülleri ile takviye
edilmesiyle, tungsten esaslı kompozit malzeme üretimi gerçekleştirilmiştir. W -
% 1 ağ. Ni - % 2 ağ. TiB2 - % 1 ağ. Y2O3
kompozisyonundan oluşan toz harmanları, normal koşullarda 12 sa mekanik olarak
öğütülerek ya da 10 dk kriyojenik ortamda öğütülerek ya da normal ve kriyojenik
şartlarda ardışık olarak öğütülerek hazırlanmıştır. Normal şartlarda öğütme
yüksek enerjili bir değirmende uygulanırken; kriyojenik şartlarda öğütme sıvı azot
ile dışarıdan çevrelenen bir sistemde yapılmıştır. Öğütülmüş tozlar hidrolik
pres kullanılarak preslenmiş ve pekiştirilen bünyeler Ar/H2 gazaltı
şartlarında 1400°C’de 1 sa sinterlenmiştir. Farklı öğütme koşullarının
sinterlenen kompozit malzemelerin mikroyapısı ve özellikleri üzerindeki etkisi
incelenmiştir. Sinterlenme sonrasında, baskın W fazına ek olarak düşük mikarda
WB ve NiW fazları oluşumu gözlemlenmiştir. Normal şartlarda öğütme sonrası
uygulanan kriyojenik öğütme, sinter malzemelerin mikroyapısındaki TiB2
ve Y2O3 partiküllerin topaklanmasının yok olmasına neden
olmuştur: Partiküllerin W1Ni matrisinin tane sınırlarında ve homojen olarak
mikroyapıda dağılması sağlanmıştır. Ardışık olarak öğütülmüş ve sinterlenmiş
kompozitler, numuneler arasında en yüksek rölatif yoğunluk (% 95,77) ve
mikrosertlik değerlerini (7,23 GPa) sunmuştur. Nano-indentasyon testleri
sayesinde, W matris fazının sertlik ve elastisite modül değerlerinin sırasıyla
8,9 ve 373,7 GPa değerlerine kadar iyileştirildiği kanıtlanmıştır.

Keywords

Tungsten esaslı kompozitler kriyojenik öğütme aktive edilmiş sinterleme TiB2 Y2O3

References

  • [1]. Lassner E., Schubert W.D., Tungsten: Properties, Chemistry, Technology of the Element, Alloys and Chemical Compounds, Kluwer Academic, New York, 1999.
  • [2]. Caldwell S.G., Tungsten heavy alloys, in: Lee P.W., Lacocca R. (Eds.), Powder Metal Technologies and Applications, ASM Handbook (v. 7), ASM International, Materials Park, Ohio, 1998, pp. 914–921.
  • [3]. Arshad K., Wang J., Yuan Y., Zhang Y., Zhou Z.-J. and Lu G.-H., Development of tungsten-based materials by different sintering techniques, Int. J. Refract. Met. Hard Mater., 50 (2015) 253–257.
  • [4]. Wei B., Wang Y., Zhao Y., Wang D., Song G., Fu Y. and Zhou Y., Effect of NbC content on microstructure and mechanical properties of W-NbC composites, Int. J. Refract. Met. Hard Mater., 70 (2018) 66–76.
  • [5]. Li Y., Zhang J., Luo G., Shen Q., and Zhang L., Densification and properties investigation of W-Cu composites prepared by electroless-plating and activated sintering, Int. J. Refract. Met. Hard Mater., 71 (2018) 255–261.
  • [6]. German R.M. and Munir Z.A., Enhanced low-temperature sintering of tungsten, Metall. Mater. Trans. A 7 (1976) 1873–1877.
  • [7]. Hayden H.W. and Brophy J.H., The activated sintering of tungsten with group VIII elements, J. Electrochem. Soc. 110 (1963) 805–810.
  • [8]. Song G.M., Wang Y.J. and Zhou Y., The mechanical and thermophysical properties of ZrC/W composites at elevated temperature, Mater. Sci. Eng. A-Struct. 334 (2002) 223–232.
  • [9]. Kim Y., Lee H.K., Kim E., Cheong D. and Hong S.H., Fabrication of high temperature oxides strengthened tungsten composites by spark plasma sintering process, Int. J. Refract. Met. Hard Mater. 27 (2009) 842–846.
  • [10]. Chen Y., Wu Y.C., Yu F.W. and Chen J.L., Microstructure and mechanical properties of tungsten composites co-strengthened by dispersed TiC and La2O3 particles, Int. J. Refract. Met. Hard Mater. 26 (2008) 525–529.
  • [11]. Liu W., Xue L. and Yan Y., Microstructure and mechanical properties of W-Cr-TiN composite by spark plasma sintering, Fusion Engineering and Design, 125 (2017) 503–509.
  • [12]. Ağaoğulları D., Balcı Ö., Gökçe H., Öveçoğlu M. L. and Duman I., Comparative investigations of the activated sintered W–1wt.% Ni composites reinforced with various oxide and boride particles, Int. J. Refract. Met. Hard Mater. 41 (2013) 577–584.
  • [13]. Li B., Sun Z., Hou G., Ding F., Hu P. and Yuan F., The effects of alumina reinforcement and nickel activated sintering on nanosized tungsten matrix, J.Alloy. Compd., 692 (2017) 420–426.
  • [14]. Genç A., Çoşkun S. and Öveçoğlu M.L., Microstructural characterizations of Ni activated sintered W-2 wt % TiC composites produced via mechanical alloying, J.Alloy. Compd. 497 (2010) 80–89.
  • [15]. Gökçe H., Balcı Ö., Ağaoğulları D., Demirkan Ö., Genç A., Öveçoğlu M.L. and Duman I., Characterization Investigations of W-Ni Matrix Composites Reinforced with TiB2 and La2O3, Acta Physica Polonica A, 123-2 (2013) 309–312.
  • [16]. Balcı Ö., Demirkan Ö. U., Ağaoğulları D., Gökçe H., Genç A., Öveçoğlu M. L. and Duman I., Effects of La2O3 Addition on the microstructure and properties of activated sintered W-Ni Compacts, Solid State Phenomen. 194 (2012) 217–221.
  • [17]. Munro R.G., Material properties of titanium diboride, J. Res. Natl. Inst. Stan. 105 (2000) 709-720.
  • [18]. Battabyal M., Schäublin R., Spätig P. and Baluc N., W–2wt. %Y2O3 composite: Microstructure and mechanical properties, Mat. Sci. Eng. A, 538, (2012) 53–57.
  • [19]. Genç A., Coşkun S. and Öveçoğlu M., Fabrication and properties of mechanically alloyed and Ni activated sintered W matrix composites reinforced with Y2O3 and TiB2 particles, Mater. Charact. 61-7 (2010) 740–748.
  • [20]. Çoşkun S. and Öveçoğlu M.L., Effects of Y2O3 additions on mechanically alloyed and sintered W-4 wt% SiC composites, Int. J. Refract. Met. Hard Mater. 29 (2011) 651–655.
  • [21]. Gupta V.K., Yoon D.H., Meyer H.M. and Luo J., Thin intergranular films and solidstate activated sintering in nickel-doped tungsten, Acta Mater. 55 (2007) 3131–3142.
  • [22]. Ağaoğulları D., Balcı Ö. and Öveçoğlu M. L., Effect of milling type on the microstructural and mechanical properties of W-Ni-ZrC-Y2O3 composites, Ceram. Int. 43-9 (2017) 7106–7114.
  • [23]. Back S.H., Lee G.H. and Kang S., Effect of cryomilling on particle size and microstrain in a WC-Co alloy, Mater. Trans. 46 (1) (2005) 105–110.
  • [24]. Veleva L., Oksiuta Z., Vogt U. and Baluc N. Sintering and characterization of W–Y and W–Y2O3 materials. Fusion Eng. Des. 84 (2009) 1920–1924.
  • [25]. Suryanarayana C., Mechanical alloying and milling, Prog. Mater. Sci. 46 (2001) 1–184.
  • [26]. Oliver W.C. and Pharr G.M., An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments, Journal of Materials Research 7-6 (1992) 1564–1583.
There are 26 citations in total.

Details

Primary Language English
Journal Section Engineering Sciences
Authors

Özge Balcı 0000-0001-6756-3180

Duygu Ağaoğulları 0000-0002-0623-5586

Mehmet Suat Somer 0000-0001-5606-9101

M. Lütfi Öveçoğlu 0000-0002-1536-4961

Publication Date March 22, 2019
Submission Date January 29, 2018
Acceptance Date December 25, 2018
Published in Issue Year 2019Volume: 40 Issue: 1

Cite

APA Balcı, Ö., Ağaoğulları, D., Somer, M. S., Öveçoğlu, M. L. (2019). Effect of Ambient and Cryogenic Milling on the Microstructure and Properties of Tungsten Matrix Composites Fabricated by Activated Sintering. Cumhuriyet Science Journal, 40(1), 204-212. https://doi.org/10.17776/csj.385724