scholarly journals Improvement of Mechanical Properties of Hard Metals Using Solid Solution Strengthened Metallic Binder (Co1-xWx)

2022 ◽  
Vol 60 (1) ◽  
pp. 14-25
Author(s):  
Hanjung Kwon
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Hydrogen Reduction ◽  
Hard Metal ◽  
Metallic Phase ◽  
Metallic Binder ◽  
Two Phase ◽  
Positive Role ◽  
Solid Solution Strengthening ◽  
Hard Metals

The metallic binder in WC-Co hard metals was effectively strengthened using the solid solution phases of Co and W. These metallic phases of Co and W (Co1-xWx, x<1), which consist of two kinds of structures (FCC and HCP), were successfully formed by hydrogen reduction of milled oxides mixtures (Co3O4 and WO3) at over 1000 oC. When hard metals are fabricated by pressureless sintering of mixed WC and Co1-xWx, the hard metals containing the WC2 and M6C phases (Co2W4C and Co4W2C) have brittleness, which degrades their mechanical properties, like hard metals fabricated from mixtures of WC, Co, and W. By rapidly sintering the WC-Co1-xWx hard metals for 5 min the WC2 and M6C phases were eliminated, and a two-phase (WC and the metallic phase of Co and W) region was successfully obtained. The mechanical properties of the WC-Co1-xWx hard metals showed higher values for both hardness (max. 18.8 GPa) and fracture toughness (8.5 MPa·m1/2) than conventional WC-Co hard metal (HV: 15.9 GPa, KIC: 6.9 MPa·m1/2). The enhancement in toughness was attributed to the solid solution strengthening of the metallic binder and the elimination of the WC2 and M6C phases. The suppression of grain growth due to the short duration of sintering also played a positive role in improving the hardness of the WC-Co1-xWx hard metals. The phase-controlled solid solution metallic binder could be the key material to enhance the hardness and toughness of hard metals.

Effect of W addition on microstructure and mechanical properties of Ni base dual two-phase intermetallic alloys

2015 ◽  
Vol 1760 ◽  
Author(s):  
Daisuke Edatsugi ◽  
Yasuyuki Kaneno ◽  
Hiroshi Numakura ◽  
Takayuki Takasugi
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Base Alloy ◽  
Intermetallic Alloys ◽  
Two Phase ◽  
Solid Solution Strengthening ◽  
Microstructure And Mechanical Properties ◽  
Heat Treated ◽  
Phase Intermetallic ◽  
Solution Strengthening

ABSTRACTThe effect of W addition on microstructure and mechanical properties of Ni3Al (L12) and Ni3V (D022) two-phase intermetallic alloys has been investigated. W was added to the base alloy composition, Ni75Al10V12Nb3 (at. %) in place of either Ni, Al or V. The W-added alloy ingots were heat-treated in vacuum at 1575 K for 5 h. The majority of W-added alloys showed a dual two-phase microstructures while the alloy in which 3 at. % W substituted for Ni exhibited the dual two-phase microstructure containing W solid solution dispersions. Vickers hardness was significantly enhanced by W addition, which is primarily due to solid-solution strengthening.

Effect of Ti Element on Microstructure and Properties of Cu-Cr Alloy

2015 ◽  
Vol 817 ◽  
pp. 307-311 ◽  
Author(s):  
Peng Chao Zhang ◽  
Jin Chuan Jie ◽  
Yuan Gao ◽  
Tong Min Wang ◽  
Ting Ju Li
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Spherical Shape ◽  
Precipitation Strengthening ◽  
Peak Hardness ◽  
Ti Alloy ◽  
Strengthening Mechanisms ◽  
Vacuum Melting ◽  
Solid Solution Strengthening ◽  
Solution Strengthening

The Cu-Cr and Cu-Cr-Ti alloy plates were prepared by vacuum melting and plastic deformation. The effect of slight Ti element on microstructure and mechanical properties of Cu-Cr alloy was discussed. The result shows that Cr particles with spherical shape precipitated from Cu matrix after aging. Plenty Ti atoms dissolved in the vicinity of Cr particles and there were still parts of solid solution Ti atoms in other regions. Improvements in peak hardness and softening resistance were achieved with the addition of Ti element in Cu-Cr alloy. The addition of 0.1 wt.% Ti element makes Cu-Cr alloy possess tensile strength of 565 MPa and hardness of 185.9 HV after aging at 450 °C for 120 min, which can be attributed to multiple strengthening mechanisms, i.e. work hardening, solid solution strengthening and precipitation strengthening.

Pseudoelasticity in High Strengthening Fcc Single Crystals

1996 ◽  
Vol 459 ◽  
Author(s):  
Yu.I. Chumlyakov ◽  
I. V. Kireeva ◽  
G. S. Kapasova ◽  
E. I. Litvinova
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Single Crystals ◽  
Stress Level ◽  
Deformation Mechanism ◽  
Crystal Orientation ◽  
Dispersion Hardening ◽  
Solid Solution Strengthening ◽  
Solution Strengthening ◽  
Applied Stresses

ABSTRACTIt was experimentally shown that the achievement of a high deforming stress level due to dispersion hardening and solid solution strengthening of FCC single crystals with a low stacking-fault energy leads to the deformation mechanism changing from slip to twinning, the dependence of mechanical properties on a crystal orientation and a sign of applied stresses. During deformation by twinning at T<150–300K effects of pseudoelasticity associated with elastic twinning is observed.

Mechanical Properties of Ga1–xInxAs

1985 ◽  
Vol 53 ◽  
Author(s):  
S. Guruswamy ◽  
J.P. Hirth ◽  
K.T. Faber
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
High Temperature ◽  
Strengthening Effect ◽  
Plateau Stress ◽  
Solid Solution Strengthening ◽  
Stress Region ◽  
Solution Strengthening ◽  
Concentration Levels ◽  
Undoped Gaas

ABSTRACTSubstantial solid solution strengthening of GaAs by In acting as InAs4 units has recently been predicted. This strengthening could account for the reduction of dislocation density in GaAs single crystals grown from the melt. High temperature hardness measurements up to 700ºC have been carried out on (100) GaAs and Ga0.9975 In0.0025 As wafers. Results show a significant strengthening effect in In—doped GaAs even at concentration levels of about 0.2 wt%. A temperature independent flow stress region is observed for both these alloys. The In—doped GaAs shows ahigher plateau stress level compared to the undoped GaAs. The results are consistent with the solid solution strengthening model.

The Effect of Heat Treatment on Microstructure and Mechanical Properties of ZK60 Alloy

2007 ◽  
Vol 353-358 ◽  
pp. 718-721
Author(s):  
Ding Fei Zhang ◽  
Rong Shen Liu ◽  
Jian Peng ◽  
Wei Yuang ◽  
Hong Ju Zhang
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Solid Solution ◽  
Age Hardening ◽  
Second Phase ◽  
Solid Solution Strengthening ◽  
Microstructure And Mechanical Properties ◽  
Long Time ◽  
Zk60 Alloy ◽  
Solution Strengthening

With different heat treatment, the microstructure and mechanical properties of ZK60 magnesium alloy were investigated. It can be concluded that heat treatment has great effect on mechanical properties of ZK60. With artificial aging after extruding, the precipitation of the second phase from the supersaturated solid solution significantly improved mechanical properties. It can greatly increase yield strength of ZK60 alloy, while the tensile strength has little change. For the combination of solid solution strengthening and age hardening, two opposite factors must be considered. On one hand, the solid solution strengthening and the later precipitation strengthening is good for alloy’s strength; on the other hand, the properties decrease as the grains grew under high temperature for a long time during solution heating.

scholarly journals Orientation-dependent solid solution strengthening in zirconium: a nanoindentation study

2019 ◽  
Vol 55 (10) ◽  
pp. 4493-4503 ◽  
Author(s):  
Arijit Lodh ◽  
Prita Pant ◽  
Gulshan Kumar ◽  
K. V. Mani Krishna ◽  
Raghvendra Tewari ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Finite Element ◽  
Elastic Modulus ◽  
Constitutive Relationship ◽  
Insignificant Change ◽  
Solid Solution Strengthening ◽  
Pure Zirconium ◽  
Solution Strengthening ◽  
Peak Value

AbstractOrientation-dependent solid solution strengthening was explored through a combined microtexture plus nanoindentation study. Pure zirconium (6N purity crystal-bar Zr) and commercial Zircaloy-2 were investigated for comparison. Local mechanical properties were estimated through finite element (FE) simulations of the unloading part of the nanoindentation load–displacement response. Combinations of ‘averaging’ scheme and constitutive relationship were used to resolve uncertainty of FE-extracted mechanical properties. Comparing the two grades, non-basal oriented grains showed an overall hardening and increase in elastic modulus. In contrast, insignificant change was observed for basal (or near-basal) oriented grains. The strengthening of non-basal orientations appeared via elimination of the lowest hardness/stiffness values without a shift in the peak value. Such asymmetric development brought out the clear picture of orientation-dependent solid solution strengthening in zirconium.

Optical, Thermal, and Mechanical Properties of (Y1-xScx)2O3 Transparent Ceramics

2021 ◽  
Author(s):  
Jiquan Huang ◽  
Changliang YANG ◽  
Qiufeng HUANG ◽  
Zhonghua DENG ◽  
Yun WANG ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Transparent Ceramics ◽  
Sintering Process ◽  
Vacuum Sintering ◽  
Solid Solution Strengthening ◽  
Complete Solid Solution ◽  
Wide Wavelength Range ◽  
Universal Approach ◽  
Solution Strengthening

Abstract Sesquioxides such as Y2O3 and Sc2O3 are important optical materials, but the fabrication of their transparent ceramics remains a challenge due to the ultra-high melting point of over 2400 oC. In this work, a series of (Y1-xScx)2O3 transparent ceramics were successfully fabricated by a simple vacuum sintering process without any sintering additives, and the effect of Scandium (Sc) content on the crystal structure and optical/thermal/mechanical properties were evaluated. Y2O3 and Sc2O3 form a complete solid solution with a cubic bixbyite structure. The formation of (Y1-xScx)2O3 solid solution promotes the densification of ceramics, leading to the realization of high transparency close to the theoretical transmittance over a wide wavelength range of 0.35-8 mm. In particular, the in-line transmittance in the range of 0.6-6 mm remains above 80% for (Y1-xScx)2O3 with x = 0.23-0.31, while the pristine Y2O3 and Sc2O3 are opaque. Moreover, the mechanical properties including Vickers hardness (Hv), fracture toughness (KIC), and biaxial strength (δb) are evidently enhanced due to the solid solution strengthening, while the thermal conductivity is reduced due to the reduction of photon free path. This study demonstrates that forming of solid solution is a facile and universal approach for preparing sesquioxides transparent ceramics with high optical and mechanical quality.

Mechanical Properties and Microstructure of Strip Casted Ag-27%Cu-25%Zn-3%Sn Brazing Alloy

2007 ◽  
Vol 26-28 ◽  
pp. 485-488 ◽  
Author(s):  
Kee Ahn Lee ◽  
Sung Jun Kim ◽  
Moon Chul Kim
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Solid Solution ◽  
Microstructural Analysis ◽  
Mechanical Tests ◽  
Rich Phase ◽  
Aging Heat Treatment ◽  
Solid Solution Strengthening ◽  
Solution Strengthening ◽  
Twin Roll

This work sought to examine the suitability of twin roll strip casting for Ag-27%Cu- 25%Zn-3%Sn brazing alloy (BAg-7A) and to investigate the mechanical properties and microstructure of the strip. The effect of aging heat treatment on the properties was also studied. This new manufacturing process has applications in the production of the brazing alloy. XRD and microstructural analysis of the Ag-27%Cu-25%Zn-3%Sn strip represented eutectic microstructure of a Cu-rich phase and a Ag-rich matrix regardless of heat treatment. The results of mechanical tests showed tensile strength of 470MPa, a significant enhancement; and an 18% elongation of the twin roll casted strip, due mainly to the solid solution strengthening of Zn atoms (~20%) in the Cu-rich phases. Tensile results showed gradually decreasing strengths and increasing elongation with aging heat treatment. Microstructural evolution and fractography were also investigated and related to the mechanical properties.

Microstructures and Mechanical Properties of NiAl+Mo In-Situ Eutectic Composites

1990 ◽  
Vol 194 ◽  
Author(s):  
P. R. Subramanian ◽  
M. G. Mendiratta ◽  
D. B. Miracle ◽  
D. M. Dimiduk
Keyword(s):  
Mechanical Properties ◽  
Solid Solution ◽  
Room Temperature ◽  
Composite System ◽  
Elevated Temperatures ◽  
Two Phase ◽  
Structural Applications ◽  
Temperature Fracture

AbstractThe quasibinary NiAI-Mo system exhibits a large two-phase field between NiAl and the terminal (Mo) solid solution, and offers the potential for producing in-situ eutectic composites for high-temperature structural applications. The phase stability of this composite system was experimentally evaluated, following long-term exposures at elevated temperatures. Bend strengths as a function of temperature and room-temperature fracture toughness data are presented for selected NiA1-Mo alloys, together with results from fractography observations.

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