Bending Strength and Cutting Performance of WB-Coated-Diamond/Fe-Ni Composites

Diamond particle with tungsten boride (WB) coating was synthesized by the molten salt method. Three different diamond/Fe-Ni composites made from pristine diamond, B4C coated diamond and WB coated diamond with Fe-Ni powders were prepared by powder metallurgy. The composition and microstructure of the tungsten boride coating were investigated. Both bending strength and cutting performance of the composites were investigated. Addition of the WB coating provided an increased bending strength (871.2 MPa) and relative density (93.54%), compared with the composites consist of uncoated diamond and Fe-Ni (746.8 MPa, 92.81%). Three different Fe-Ni-based impregnated diamond drill bits contained 20 vol.% pristine diamond, B4C coated diamond and WB coated diamond were manufactured by powder metallurgy, respectively. Drilling rate of bits was measured by XY-4 geological core drill on granite. The test results show that the drilling rate of bits with WB coated diamond (2.42 m/h) was 40% higher than that with pristine uncoated diamond (1.72 m/h).

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Testing and Assessing Method for the Resistance of Wood-Plastic Composites to the Action of Destroying Fungi

Materials ◽

10.3390/ma14030697 ◽

2021 ◽

Vol 14 (3) ◽

pp. 697

Author(s):

Anna Wiejak ◽

Barbara Francke

Keyword(s):

Bending Strength ◽

Test Results ◽

Negative Effects ◽

Destructive Effect ◽

Wood Plastic Composites ◽

Plastic Composites ◽

Wood Polymer ◽

Proposed Modification ◽

Assessing Method ◽

Biological Corrosion

Durability tests against fungi action for wood-plastic composites are carried out in accordance with European standard ENV 12038, but the authors of the manuscript try to prove that the assessment of the results done according to these methods is imprecise and suffers from a significant error. Fungi exposure is always accompanied by high humidity, so the result of tests made by such method is always burdened with the influence of moisture, which can lead to a wrong assessment of the negative effects of action fungus itself. The manuscript has shown a modification of such a method that separates the destructive effect of fungi from moisture accompanying the test’s destructive effect. The functional properties selected to prove the proposed modification are changes in the mass and bending strength after subsequent environmental exposure. It was found that intensive action of moisture measured in the culture chamber of about (70 ± 5)%, i.e., for 16 weeks, at (22 ± 2) °C, which was the fungi culture, which was accompanying period, led to changes in the mass of the wood-plastic composites, amounting to 50% of the final result of the fungi resistance test, and changes in the bending strength amounting to 30–46% of the final test result. As a result of the research, the correction for assessing the durability of wood-polymer composites to biological corrosion has been proposed. The laboratory tests were compared with the products’ test results following three years of exposure to the natural environment.

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Effect of Spark Plasma Sintering on the Microstructure Evolution and Properties of M3:2 High-Speed Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.788.329 ◽

2014 ◽

Vol 788 ◽

pp. 329-333

Author(s):

Rui Zhou ◽

Xiao Gang Diao ◽

Jun Chen ◽

Xiao Nan Du ◽

Guo Ding Yuan ◽

...

Keyword(s):

Powder Metallurgy ◽

Spark Plasma Sintering ◽

High Speed ◽

Bending Strength ◽

Sintering Temperature ◽

High Speed Steel ◽

Continuous Heating ◽

Plasma Sintering ◽

Spark Plasma ◽

The Impact

Effects of sintering temperatures on the microstructure and mechanical performance of SPS M3:2 high speed steel prepared by spark plasma sintering was studied. High speed steel sintering curve of continuous heating from ambient temperature to 1200°C was estimated to analyze the sintering processes and sintering temperature range. The sintering temperature within this range was divided into groups to investigate hardness, relative density and microstructure of M3:2 high-speed steel. Strip and quadrate carbides were observed inside the equiaxed grains. SPS sintering temperature at 900°C can lead to nearly full densification with grain size smaller than 20μm. The hardness and bending strength are higher than that of the conventionally powder metallurgy fabricated ones sintered at 1270°C. However, fracture toughness of the high speed steel is lower than that of the conventional powder metallurgy steels. This can be attributed to the shape and distribution of M6C carbides which reduce the impact toughness of high speed steels.

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The Effect of Oxygen Addition on Oxidation Resistance and Cutting Performance of Si3N4 Ceramics

Materials Science Forum ◽

10.4028/www.scientific.net/msf.534-536.1089 ◽

2007 ◽

Vol 534-536 ◽

pp. 1089-1092

Author(s):

Mituyoshi Nagano ◽

Hideaki Sano ◽

Shigeya Sakaguchi ◽

Guo Bin Zheng ◽

Yasuo Uchiyama

Keyword(s):

Bending Strength ◽

Cutting Tools ◽

Cutting Performance ◽

Al2o3 Content ◽

High Wear Resistance ◽

Composition Analysis ◽

Performance Improvements ◽

Oxygen Addition ◽

Effect Of Oxygen ◽

Si3n4 Ceramics

The effect of oxygen addition on oxidation behavior of the β-Si3N4 ceramics with 5 mass% Y2O3 and 2 or 4 mass% Al2O3 was investigated by performing oxidation tests in air at 1300° to 1400°C and cutting performance tests. These tests were intended to clarify their ware resistance as cutting tools. The results of mass change, SEM observation and composition analysis of the specimens before and after oxidation test showed that as the Al2O3 content in the β-Si3N4 ceramics increased, mass changes resulted higher oxidation during which process pores and cracks formed due to the release of N2 gas. The values of hardness and bending strength of the specimens with relatively small amount of 2 mass% Al2O3, which formed solid solution in the Si3N4 structure [Si6-zAlzOzN8-z (z = 0.1)], showed larger than those of the specimen with 4 mass% Al2O3 (z = 0.2). The specimens group added with Al2O3 of 2 mass% (Z = 0.1) also showed high wear resistance. From this, we could conclude that the mechanical properties of β-Si3N4 ceramics depending on oxygen introduction is much effective on cutting performance improvements of the cutting performance of β-Si3N4 ceramics.

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Sintered High Carbon Steels: Effect of Thermomechanical Treatments on their Mechanical and Wear Performance

Materials Science Forum ◽

10.4028/www.scientific.net/msf.591-593.271 ◽

2008 ◽

Vol 591-593 ◽

pp. 271-276 ◽

Cited By ~ 1

Author(s):

M.A. Martinez ◽

R. Calabrés ◽

J. Abenojar ◽

Francisco Velasco

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Powder Metallurgy ◽

Thermomechanical Treatment ◽

Bending Strength ◽

Carbon Steels ◽

Tool Steels ◽

High Carbon ◽

Wear Performance ◽

Metallographic Study

In this work, ultrahigh carbon steels (UHCS) obtained by powder metallurgy with CIP and argon sintered at 1150°C. Then, they were rolled at 850 °C with a reduction of 40 %. Finally, steels were quenched at 850 and 1000 °C in oil. In each step, hardness, bending strength and wear performance were evaluated. Obtained results are justified with a metallographic study by SEM. Both mechanical properties and wear resistance are highly favoured with the thermomechanical treatment that removes the porosity of the material. Moreover, final quenching highly hardens the material. The obtained material could be used as matrix for tool steels.

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Preparation and Properties of SiC/Phenolic Resin for the Heat of LED

Materials Science Forum ◽

10.4028/www.scientific.net/msf.848.454 ◽

2016 ◽

Vol 848 ◽

pp. 454-459

Author(s):

Cong Wu ◽

Kang Zhao ◽

Yu Fei Tang ◽

Ji Yuan Ma

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Powder Metallurgy ◽

Phenolic Resin ◽

Bending Strength ◽

Experimental Results ◽

Low Thermal Conductivity ◽

Industry Standard ◽

Insulation Performance

In order to solve the problem that low thermal conductivity of the plastics for the heat of LED, SiC/Phenolic resin for the heat of LED were fabricated combining powder metallurgy. The effects of particles diameters, content and adding nanoparticles on thermal conductivity of the fabricated composites were investigated, the mechanical properties were also characterized. The experimental results showed that the materials were obtained, and the insulation performance of the fabricated SiC/Phenolic resin was higher than the industry standard one, the thermal conductivity reached 4.1W/(m·k)-1. And the bending strength of the fabricated composites was up to 68.11MPa. The problem of low thermal conductivity of the material is expected to be solved. In addition, it is meaningful for improving LED life.

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STUDI KUAT LENTUR BETON DENGAN BAHAN TAMBAH SERAT ABAKA

Teras Jurnal ◽

10.29103/tj.v11i1.364 ◽

2021 ◽

Vol 11 (1) ◽

pp. 53

Author(s):

Yudi Pranoto ◽

Lina Halim ◽

Anung Sudibyo

Keyword(s):

Flexural Strength ◽

Bending Strength ◽

Fiber Content ◽

Mix Design ◽

Fine Aggregate ◽

Test Results ◽

Concrete Mix Design ◽

Banana Tree ◽

Flexible Fiber ◽

Test Objects

Abstrak Serat abaka merupakan serat yang awet dan lentur yang diambil dari pohon pisang. Serat ini masih sangat jarang dimanfaatkan, sementara di Indonesia serat abaka bisa ditemukan di mana mana. Tujuan penelitian ini adalah untuk mengetahui sejauh mana pengaruh serat abaka terhadap kuat lentur beton. Penelitian ini diawali dengan studi literature, pengujian material (Agregat halus, agregat kasar, semen dan serat abaka), mix design beton, pembuatan benda uji, perawatan dan dilanjutkan dengan pengujian kuat lentur beton serta terakhir dilakukan analisis hasil pengujian. Dari hasil pengujian didapatkan kuat lentur maksmum terjadi pada kadar serat abaka sebesar 0,6% dengan kuat lentur 3,75 MPa, sedangkan kuat lentur terkecil terjadi pada kadar serat abaka 0% dengan kuat lentur 3,34 MPa. Kata kunci: serat abaka, kuat lentur, mix deisgn Abstract Abaca fiber is a durable and flexible fiber taken from the banana tree. This fiber is still very rarely used, while in Indonesian abaca fiber can be found everywhere. The purpose of this study was to determine the extent of the influence of abaca fiber on the flexural strength of concrete. This research begins with literature studies, material testing (fine aggregate, coarse aggregate, cement, and abaca fiber), concrete mix design, manufacture of test objects, curing, and continues with concretes flexural strength testing and finally an analysis of the test results. From the test results, it founded that the maximum flexural strength occurred at the abaca fiber content of 0.6% with a bending strength of 3.75 MPa, and the smallest flexural strength occurred at 0% abaca fiber content with a flexural strength of 3.34 MPa. Keywords: Abaka fiber, flexural strength, mix design

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EFFECT OF CALCIUM SULFOALUMINATE ADDITIVE ON LINEAR DEFORMATION AT DIFFERENT HUMIDITY AND STRENGTH OF CEMENT MORTARS

Inżynieria Bezpieczeństwa Obiektów Antropogenicznych ◽

10.37105/iboa.64 ◽

2020 ◽

Author(s):

Kadhim Abdulwahid Al-Musawi ◽

Kottayil Bindhu Abraham ◽

Tatsiana Potses ◽

Sergey Leonovich ◽

Natallia Kalinouskaya ◽

...

Keyword(s):

Bending Strength ◽

High Humidity ◽

Test Results ◽

High Quality ◽

Linear Deformation ◽

Calcium Sulfoaluminate ◽

Environmental Humidity ◽

Cement Mortars ◽

Under Construction ◽

Very High

The effect of calcium sulfoaluminate additives (CSA) on the compression and bending strength of mortar, as well as linear deformation of prism samples at different environmental humidity was studied. Test results indicate that bending strength of mortars with CSA and the referent at the age of 28 days are practically equal. Compressive strength of mortars with CSA reduced by 20 ... 23% for all dosages of CSA. Relative linear deformations depend on the humidity of the environment. At a humidity of 100%, the relative linear deformations are positive and the expansion increases with increasing dosage of the expanding additive. When hardening in dry air at a humidity of 55%, the greatest shrinkage deformations were for mortars with CSA. We can conclude that the expanding effect of CSA is fully manifested at high humidity, i.e. under construction conditions, this means very high-quality moisture care for concrete structures.

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Bending Strength of Al2O3 Ceramics for Textiles Machinery and Elastic Wave Characteristics by Wavelet Analysis

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.345 ◽

2007 ◽

Vol 353-358 ◽

pp. 345-348

Author(s):

Ki Woo Nam ◽

B.G. Ahn ◽

M.K. Kim ◽

C.S. Son ◽

Jin Wook Kim ◽

...

Keyword(s):

Elastic Wave ◽

Bending Strength ◽

Test Results ◽

Composite Ceramics ◽

Bending Tests ◽

Three Point Bending ◽

Wave Signal ◽

Al2o3 Composite ◽

Signal Characteristics ◽

Optimized Conditions

The optimized conditions of pressureless sintering were investigated in order to obtain the bending strength and the elastic wave signal of Al2O3 composite ceramics for textiles machinery. As sintering conditions, a temperature range from 1400°C to 1700°C and time from 30 minutes to 150 minutes were applied. Three-point bending tests were conducted on the sintered materials to obtain the strength property. From the test results, the optimum sintering condition was 1600°C, 100 minutes. Al2O3 composite ceramics showed that the elastic wave signal characteristics had a regular correlativity between the optimum sintering temperature and time as well as the maximum bending strength.

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Wear Characteristics of Polycrystalline Diamond Compact Drill Bits in Small Diameter Rock Drilling

Journal of Energy Resources Technology ◽

10.1115/1.3231231 ◽

1985 ◽

Vol 107 (4) ◽

pp. 534-542 ◽

Cited By ~ 9

Author(s):

C. L. Hough ◽

B. Das

Keyword(s):

Small Diameter ◽

Polycrystalline Diamond ◽

Wear Test ◽

Test Results ◽

Failure Characteristics ◽

Wear Characteristics ◽

Drill Bits ◽

Rotary Speed ◽

Polycrystalline Diamond Compact ◽

Single Material

The wear characteristics of polycrystalline diamond compact (PDC) drill bits were investigated in the context of drilling small holes in a hard abrasive medium. An efficient method for measuring wear of the PDC drill bits was developed. The wear test results were grouped or categorized in terms of rotary speed, feed and wear or failure characteristics. Contrary to the three classical wear phases (break-in, uniform wear and rapid breakdown) of the single material cutters, four distinctive wear phases were formed for the PDC cutters: I–break-in, II–diamond wear, III–carbide wear, and IV–rapid breakdown. The characteristics of the wear phases were identified and some suggestions were made to alleviate the wear problem.

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Fracture Toughness Analysis of Epoxy-Recycled Rubber-Based Composite Reinforced with Graphene Nanoplatelets for Structural Applications in Automotive and Aeronautics

Polymers ◽

10.3390/polym12020448 ◽

2020 ◽

Vol 12 (2) ◽

pp. 448 ◽

Cited By ~ 3

Author(s):

Alaeddin Burak Irez ◽

Emin Bayraktar ◽

Ibrahim Miskioglu

Keyword(s):

Fracture Toughness ◽

Building Materials ◽

Bending Strength ◽

Mechanical Test ◽

Graphene Nanoplatelets ◽

Test Results ◽

Toughening Mechanisms ◽

Structural Applications ◽

Recycled Rubber ◽

Cost Efficient

This study proposes a new design of lightweight and cost-efficient composite materials for the aeronautic industry utilizing recycled fresh scrap rubber, epoxy resin, and graphene nanoplatelets (GnPs). After manufacturing the composites, their bending strength and fracture characteristics were investigated by three-point bending (3PB) tests. Halpin–Tsai homogenization adapted to composites containing GnPs was used to estimate the moduli of the composites, and satisfactory agreement with the 3PB test results was observed. In addition, 3PB tests were simulated by finite element method incorporating the Halpin–Tsai homogenization, and the resulting stress–strain curves were compared with the experimental results. Mechanical test results showed that the reinforcement with GnPs generally increased the modulus of elasticity as well as the fracture toughness of these novel composites. Toughening mechanisms were evaluated by SEM fractography. The typical toughening mechanisms observed were crack deflection and cavity formation. Considering the advantageous effects of GnPs on these novel composites and cost efficiency gained by the use of recycled rubber, these composites have the potential to be used to manufacture various components in the automotive and aeronautic industries as well as smart building materials in civil engineering applications.

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