Dependence of the yield strength of WC-Co hard alloys on their cobalt content and tungsten carbide grain size

1974 ◽  
Vol 13 (5) ◽  
pp. 413-415
Author(s):  
V. A. Ivensen ◽  
O. N. Éiduk ◽  
V. A. Chistyakova
1978 ◽  
Vol 100 (1) ◽  
pp. 74-76 ◽  
Author(s):  
J. Peck

Investigation shows that there is a preferred cobalt content for a given hardness of a cemented carbide insert when used in a bit which is drilling iron ore. Two parameters determine the hardness of a cemented carbide: cobalt percent and tungsten carbide grain size. By manipulating these two parameters, a number of cemented carbide materials can be made which have the same hardness. Three iron-ore drilling tests have been conducted where test bits contained materials having essentially the same hardness, but where the materials were varied through a range of cobalt content and tungsten carbide grain size. Graphs are presented which depict the effect on fracture resistance of varying the cobalt content-tungsten carbide grain size. In each test, one material showed superior fracture resistance. The test bits drilled iron ores such as hematite or taconite.


2015 ◽  
Vol 1114 ◽  
pp. 13-21 ◽  
Author(s):  
Mario Rosso ◽  
Ildiko Peter ◽  
Federico Gobber

Circular saw blades are used exclusively for cut-off work, ranging from small manual feed operations, up to very large power fed saws commonly used for sectioning stock as it comes from a rolling mill or other manufacturing processes for long products. The teeth profile, as well as the tooth configuration are of fundamental importance for the blade performances; through a combination of blade rigidity and grinding wheel condition a good quality surface finish is attained for tools of commercial standard. The materials used for the production of circular saw blades are ranging from high speed steel to cemented carbides. In particular, cemented carbides, being characterized by high hardness and strength, are used in applications where materials with high wear resistance and toughness are required. The main constituents of cemented carbides are tungsten carbide and cobalt. Tungsten carbide imparts the alloys the necessary strength and wear resistance, whereas cobalt contributes to the toughness and ductility of the alloys. The WC-Co alloys are tailored for specific applications by the proper choice of tungsten carbide grain size and the cobalt content. The grain size of the tungsten carbide in WC-Co varies from about 40 µm to around 0.3 µm, the cobalt content from 3 to 30 wt%. The coarse grained hardmetals are mainly used in mining applications, the smallest grain size being about 3 µm and the minimum cobalt content 6 wt%. The grain size of tungsten carbide in the metal cutting industry, as well as for universal applications lies in the range of 1-2 µm. However, with the advent of near net shape manufacturing and thin walled components, the use of submicron carbide is growing, since their high compressive strength and abrasive wear resistance can be used to produce tools with a sharp cutting edge and a large positive rake angle.In this invited paper, a general overview on the actual trends in the choice of the best material when cutting special alloys will be presented and discussed. Based on the recent and past literature some examples of their up-to-date application, such as circular saws used to cut stainless steels and some high strength alloys, are talk over.


2014 ◽  
Vol 966-967 ◽  
pp. 80-86
Author(s):  
Varunee Premanond ◽  
Onnjira Diewwanit

The objective of this work is to investigate the tribological behavior between WC-Co cemented carbide and austenitic stainless steel under repeated rotation sliding. Influences of cobalt content of commercial grade cemented tungsten carbide on friction coefficient and material transfer phenomena have been explored. Three grades of commercial WC-Co cemented carbide with similar medium WC grain size were employed; WC-12Co, WC-14Co and WC-19Co. The average grain size were ranges between 0.85-1.1 μm and the hardness of about 86-88 HRA have been given by the material maker. The composition analysis and the average grain size of tungsten carbide have been rechecked. Furthermore, the carbide grain size distribution was recorded and the fracture toughness was calculated for each WC-Co grade. The experiments were carried out using ball on disk test. The ball was made from SUS304 grade and the disk was fabricated by 3 grades of WC-Co cemented carbide. The friction coefficient was measured under dry sliding. The characteristics of contact surfaces were explored on the ball as well as on the disk after tests to reveal the presence of a metallic transfer on the WC-Co cemented carbide disk and the wear scar on the ball. The measurement results of wear volume on the stainless steel ball disclosed that maximum wear rate was found from the stainless steel ball rub against WC-19Co tool material.


2019 ◽  
Vol 26 (09) ◽  
pp. 1950051
Author(s):  
YUANPING HE ◽  
YU-XIAO CUI ◽  
FANG-HONG SUN

In this study, the diamond films are deposited on tungsten carbide substrates with 10[Formula: see text]wt.% Co via hot filament chemical vapor deposition (HFCVD). Amorphous SiC (a-SiC) interlayers with various thicknesses are fabricated between the diamond films and tungsten carbide substrates via precursor pyrolysis to promote the adhesion and friction performance of diamond films. Indentation tests are performed to evaluate the adhesion of the as-fabricated diamond films, which show that the a-SiC interlayers can greatly improve the adhesive strength between diamond films and tungsten carbide substrates with 10[Formula: see text]wt.% Co. Moreover, the thickness of a-SiC interlayer is of great importance for the effectiveness on the film–substrate adhesion enhancement. The optimum thickness of a-SiC interlayer is 1[Formula: see text][Formula: see text]m. Afterwards, ball-on-disc experiments are chosen to check the tribological properties of the as-fabricated a-SiC interlayered diamond film specimen with the optimum interlayer thickness, which exhibits lower friction coefficient than the conventional diamond film with no interlayer.


2014 ◽  
Vol 9 (9-10) ◽  
pp. 555-558
Author(s):  
L. G. Khvostantsev ◽  
G. V. Borovskii ◽  
V. V. Brazhkin ◽  
L. A. Laitsan ◽  
V. G. Borovskii

1996 ◽  
Vol 34 (9-10) ◽  
pp. 551-554 ◽  
Author(s):  
M. S. Koval'chenko ◽  
A. V. Paustovskii ◽  
V. N. Minakov ◽  
B. M. Boleiko ◽  
N. A. Yurchuk ◽  
...  

Metals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1148 ◽  
Author(s):  
Roman Husák ◽  
Hynek Hadraba ◽  
Zdeněk Chlup ◽  
Milan Heczko ◽  
Tomáš Kruml ◽  
...  

Oxide dispersion-strengthened (ODS) materials contain homogeneous dispersions of temperature-stable nano-oxides serving as obstacles for dislocations and further pinning of grain boundaries. The strategy for dispersion strengthening based on complex oxides (Y-Hf, -Zr, -Ce, -La) was developed in order to refine oxide dispersion to enhance the dispersion strengthening effect. In this work, the strengthening of EUROFER steel by complex oxides based on Y and elements of the IIIB group (lanthanum, scandium) and IVB group (cerium, hafnium, zirconium) was explored. Interparticle spacing as a dispersoid characteristic appeared to be an important factor in controlling the dispersion strengthening contribution to the yield strength of ODS EUROFER steels. The dispersoid size and average grain size of ODS EUROFER steel were altered in the ranges of 5–13 nm and 0.6–1.7 µm, respectively. Using this strategy, the yield strength of the prepared alloys varied between 550 MPa and 950 MPa depending on the doping element.


Wear ◽  
2021 ◽  
pp. 203788
Author(s):  
Shaogang Cui ◽  
Shenglu Lu ◽  
Kiet Tieu ◽  
Ganesh Kumar Meenashisundaram ◽  
Long Wang ◽  
...  

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