An outlook on the influence on mechanical properties of AZ31 reinforced with graphene nanoparticles using powder metallurgy technique for biomedical application

AbstractMicrostructural changes that result in relevant improvements in mechanical properties and electrochemical behavior can be induced using different sintering conditions of ASTM F75 cobalt alloys during their processing using powder metallurgy technique. It has been observed that the increase in carbon and nitrogen content improves corrosion resistance and mechanical properties as long as the precipitation of carbides and nitrides is avoided, thanks to the use of rapid cooling in water after the sintering stage. In addition, the reduction of the particle size of the powder improves hardness and resistance to corrosion in both acid medium with chlorides and phosphate-buffered medium that simulates the physiological conditions for its use as a biomaterial. These results lead to increased knowledge of the role of carbon and nitrogen content in the behavior displayed by the different alloys studied.

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Wide-Gap Brazing of K417G Alloy Assisted by In Situ Precipitation of M3B2 Boride Particles

Materials ◽

10.3390/ma13143140 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3140 ◽

Cited By ~ 1

Author(s):

Zhun Cheng ◽

Xiaoqiang Li ◽

Minai Zhang ◽

Shengguan Qu ◽

Huiyun Li

Keyword(s):

Mechanical Properties ◽

Powder Metallurgy ◽

Room Temperature ◽

Distribution Characteristics ◽

Powder Metallurgy Technique ◽

Dispersion Strengthening ◽

Eutectic Transformation ◽

Wide Gap ◽

Strength And Plasticity

In this study, K417G Ni-based superalloy with a 20-mm gap was successfully bonded at 1200 °C using powder metallurgy with a powder mixture. The results indicated that the microstructure and mechanical properties of the as-bonded alloy were highly dependent on the brazing time (15–45 min), mainly due to the precipitation and distribution characteristics of M3B2 boride particles. Specifically, alloy brazed for 30 min exhibited desirable mechanical properties, such as a high tensile ultimate strength of 971 MPa and an elongation at fracture of 6.5% at room temperature, exceeding the balance value (935 MPa) of the base metal. The excellent strength and plasticity were mainly due to coherent strengthening and dispersion strengthening of the in situ spherical and equiaxed M3B2 boride particles in the γ + γ′ matrix. In addition, the disappearance of dendrites and the homogenization of the microstructure are other factors that cannot be excluded. This powder metallurgy technique, which can avoid the eutectic transformation of traditional brazing, provides a new effective method for wide-gap repair of alloy materials.

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Effects of SiO2 Particles in Mechanical Properties of Iron Composite

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.465-466.886 ◽

2013 ◽

Vol 465-466 ◽

pp. 886-890

Author(s):

Adibah Amir ◽

Othman Mamat

Keyword(s):

Mechanical Properties ◽

Powder Metallurgy ◽

Fine Particles ◽

Sintering Temperature ◽

Silica Particles ◽

Milling Process ◽

Powder Metallurgy Technique ◽

Temperature Changes ◽

Different Temperatures

Tronohs raw sand was converted into fine silica particles via a series of milling process. Addition of these fine particles into iron composite was found to modify its mechanical properties. The composite was prepared using powder metallurgy technique with varying percentage of silica particles; 5, 10, 15, 20 and 25wt%. The composites were sintered at three different temperatures; 1000° C, 1100° C and 1200° C to find the most suitable sintering temperature. Changes in density and hardness were observed. The results showed that composite consist of 20wt% silica particles and sintered at 1100° C exhibits best improvement.

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Characterization and Properties of Iron/Silica-Sand-Nanoparticle Composites

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.316-317.97 ◽

2011 ◽

Vol 316-317 ◽

pp. 97-106 ◽

Cited By ~ 6

Author(s):

Tahir Ahmad ◽

Othman Mamat

Keyword(s):

Mechanical Properties ◽

Electrical Conductivity ◽

Powder Metallurgy ◽

Metal Matrix ◽

Silica Sand ◽

Particulate Composites ◽

Powder Metallurgy Technique ◽

Superior Mechanical Properties ◽

Iron Based ◽

Nanoparticle Composites

Metal matrix-particulate composites fabricated by using powder metallurgy possess a higher dislocation density, a small sub-grain size and limited segregation of particles, which, when combined, result in superior mechanical properties. The present study aims to develop iron based silica sand nanoparticles composites with improved mechanical properties. An iron based silica sand nanoparticles composite with 5, 10, 15 and 20 wt.% of nanoparticles silica sand were developed through powder metallurgy technique. It was observed that by addition of silica sand nanoparticles with 20 wt.% increased the hardness up to 95HRB and tensile strength up to 690MPa. Sintered densities and electrical conductivity of the composites were improved with an optimum value of 15 wt.% silica sand nanoparticles. Proposed mechanism is due to diffusion of silica sand nanoparticles into porous sites of the composites.

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Effect of Processing Parameters on the Microstructure and Mechanical Behaviour of Nano Bioceramic

ASME 2008 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2008-193076 ◽

2008 ◽

Author(s):

Xueran Liu ◽

Ahmed R. El-Ghannam

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Powder Metallurgy ◽

Stress Shielding ◽

Processing Parameters ◽

Processing Conditions ◽

Powder Metallurgy Technique ◽

Regenerative Capacity ◽

Structural Support ◽

Superior Mechanical Properties

Silica-calcium phosphate nanocomposite (SCPC) has a superior bone regenerative capacity and resorbability when compared to hydroxyapatie (HA) and bioactive glass [1–2]. Synthesis of SCPC bioceramics with superior mechanical properties has been an important and challenging issue. Ideally, the mechanical strength of the orthopedic implantat should be comparable to that of the host-bone in order to provide structural support and minimize stress shielding. The compressive strength of trabecular bone ranges from 2–12 MPa and that of cortical bone varies in the range of 100–230 MPa [3]. The aim of the present study is to study the effect of processing parameters on the mechanical properties of SCPC cylinders prepared by powder metallurgy technique. The mechanical properties were correlated to the microstructure of SCPC prepared under different processing conditions.

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