A correlation between nano and micro-hardness properties of TiN nanoparticles strengthened SAF 2205

4th International Conference on Structural NanoComposites

Mphahlele, M.R.^1 ; Oke, S.R.^1 ; Ige, O.O.^1^2 ; Falodun, O.E.^1 ; Obadele, B.A.^1 ; Olubambi, P.A.^1 ; Shongwe, M.B.^3

Centre for Nanomechanics and Tribocorrosion, University of Johannesburg, Johannesburg, South Africa^1

Department of Materials Science and Engineering, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria^2

Department of Chemical, Metallurgical and Materials Engineering, Tshwane University of Technology, Pretoria, South Africa^3

关键词: Dislocation motion;    Grain hardness;    Linear relation;    Linear relationships;    Nanoand micro hardness;    Strengthening effect;    TiN nanoparticles;    Vickers;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/499/1/012009/pdf
DOI  :  10.1088/1757-899X/499/1/012009

来源: IOP

【 摘 要 】

This work studied the correlation between Vickers and nano-hardness of SAF 2205 reinforced with TiN nanoparticles for the convenience of assessing its mechanical properties. Spark plasma sintering was used to fabricate the composites. Micro and nanoindentations were performed to determine micro and nanohardness values of the fabricated composite. Optical microscope was used to assess the microstructure. The microstructure revealed that the TiN dominated the ferrite/ferrite, ferrite/austenite and austenite/austenite grain boundaries. The micro and nanohardness at the TiN dominated grain boundaries were higher compared to the grain hardness. Hardness also increased considerably as the TiN nanoparticles increases. This is also owed to the strengthening effect played by TiN at the grain boundaries by disrupting dislocation motion in the composite. The determined Vickers hardness was plotted as a function of the corresponding nanohardness, a good linear relation was found between Vickers hardness and nanohardness. A linear relationship (HV = 215.15 + 15.03Hnano) was established which indicates that there is no difference in behavior for the Vickers hardness and nanohardness.