Effect of Spheroidizing Annealing Time on Microstructure and Hardness of GCr15 Bearing Steel

In order to shorten the spheroidizing annealing time, the effects of annealing time on microstructure and hardness of GCr15 have been researched by using OM, SEM and Vickers hardness tester. The original microstructural constituent of bearing steel is pearlite and cementite. Prolonged time at 805°Cwill decrease the number and increase size of cementite particles. After incomplete austenization at 805°C, prolonged time at 720°C induces increase of particle size, and uniform distribution of divorced pearlite. The hardness of specimens treated with different spheroidization process fluctuates around 200HV, and is equivalent to that with conventional spheroidization process. It is realizable to shorten the annealing time on the premise of good quality of bearing steel.

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The Effect of SiC Particle Size on the Microstructure and Hardness of SiCp/Cu Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.997.442 ◽

2014 ◽

Vol 997 ◽

pp. 442-445

Author(s):

Ming Hu ◽

Li Li Tang ◽

Lin Shan ◽

Yun Long Zhang

Keyword(s):

Particle Size ◽

Vickers Hardness ◽

Copper Matrix ◽

X Ray Diffraction ◽

Chemical Plating ◽

Hardness Tester ◽

Sic Particles ◽

Structure Morphology ◽

Hot Press Sintering ◽

Sic Particle

The chemical plating technology was applied in order to improve the weaker wettability between the copper and SiC particles for electronic packaging applications. The hot-press sintering technique was executed to fabricate SiCp/Cu composites. The influence of SiC particles size on the phase constitute, micro-structure morphology and vickers hardness were investigated in details by means of X-ray diffraction, scanning electron microscope and vickers hardness tester. The results showed that SiC particle were distributed in copper matrix uniformly and interface was clear. The relative density and vickers hardness of SiCp/Cu composites increased as SiC particle size enhanced.

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PERBANDINGAN KUALITAS MATERIAL BEARING MERK SKF, FMB, NKK, DAN JAL TERHADAP TERHADAP SIFAT FISIS DAN MEKANIS

Media Mesin: Majalah Teknik Mesin ◽

10.23917/mesin.v18i2.5241 ◽

2017 ◽

Vol 18 (2) ◽

Author(s):

Masyrukan Masyrukan ◽

Ngafwan Ngafwan ◽

Taufik Surya Nugroho

Keyword(s):

Surface Roughness ◽

Vickers Hardness ◽

Ball Bearing ◽

Hardness Testing ◽

Test Analysis ◽

Hardness Tester ◽

Microstructure Observation ◽

Materials Used ◽

Working Parameters

ABSTRAK Penelitian ini bertujuan untuk mengetahui kualitas bahan yang digunakan pada empat merk bearing (SKF, FMB, NKK, dan JAL) berdasarkan data-data pengujian sifat- sifat mekanik serta struktur intern (struktur mikro) pada benda uji tersebut dan dapat membandingkan ketahanan dan kekuatan keempat merk bearing tersebut berdasarkan analisis pengujian terhadap kegunaannya. Pengujian yang dilakukan meliputi pengujian kekerasan menggunakan alat Micro Vickers Hardness Tester, pengamatan struktur mikro menggunakan alat Olympus Metallurgical Microscope dan Olympus Phtomicrographics Systems, serta pengujian kekasaran permukaan menggunakan alat Surfcorder. Pengujian kekerasan maupun struktur mikro dilakukan pada bagian cincin luar bantalan (outer bearing) dan ball bearing. Sedangkan pengujian kekasaran permukaan hanya pada bagian outer bearing. Setelah dilakukan semua pengujian dapat disimpulkan bahwa berdasarkan kekuatan, kekerasan (ketahanan aus) serta kekasaran permukaan pada bagian outer bearing dan ball bearing maka merk yang memenuhi kualitas optimum adalah merk FMB karena sudah mencukupi dengan parameter kerja bantalan sehingga membuat umur pakai lebih panjang pada aspek penggunaan yang sama. Kata kunci: bearing, kekerasan, struktur mikro, kekasaran permukaan ABSTRACT This study aims to determine the quality of materials used in four bearing brands (SKF, FMB, NKK, and JAL) based on data testing of mechanical properties as well as internal structure (micro structure) on the specimens and can compare the endurance and the strength of the four brands bearings based on the test analysis of its usefulness. The tests include hardness testing using the Micro Vickers Hardness Tester tool, microstructure observation using Olympus Metallurgical Microscope and Olympus Phtomicrographics Systems, and surface roughness testing using Surfcorder tool. Hardness testing and microstructure are performed on outer bearing and ball bearing parts. While the surface roughness testing only on the outer bearing. After all tests, it can be concluded that based on strength, hardness (wear resistance) and surface roughness on outer bearing and ball bearings, the brand that meets the optimum quality is the FMB brand because it is sufficient with the bearing working parameters that make longer life on the same aspect of use. Keywords: bearing, strengthness, microstructure, surface roughness

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The Influence of Extruded Sugar Beet Pulp on Cookies' Nutritional, Physical and Sensory Characteristics

Sustainability ◽

10.3390/su13095317 ◽

2021 ◽

Vol 13 (9) ◽

pp. 5317

Author(s):

Sonja Simić ◽

Jovana Petrović ◽

Dušan Rakić ◽

Biljana Pajin ◽

Ivana Lončarević ◽

...

Keyword(s):

Particle Size ◽

Sugar Beet ◽

Dietary Fiber ◽

Wheat Flour ◽

Nutritional Quality ◽

Sugar Beet Pulp ◽

Sensory Characteristics ◽

Total Dietary Fiber ◽

Beet Pulp

Sugar beet pulp (SBP) is a by-product of the sugar industry in which the dietary fiber content ranges from 73% to 80%. Compared to cereal fibers mainly used in biscuit production, sugar beet fibers are gluten free and have a perfect ratio of 2/3 insoluble fiber. In this work, sugar beet pulp was extruded with corn grits (ratios of corn grits to sugar beet pulp in extrudates were 85:15, 70:30, and 55:45), and the obtained sugar beet pulp extrudates (SBPEs) were used for improving the nutritional quality of cookies. The wheat flour in cookies was replaced with SBPEs in the amount of 5, 10, and 15%. The influence of three factors (the percentage of sugar beet pulp in the SBPEs, the size of the SBPE particles, and the percentage of wheat flour substituted with SBPEs) and their interactions on the nutritional quality of cookies, as well as their physical and sensory characteristics are examined using the Box–Behnken experimental design. The addition of extruded sugar beet pulp (SBPEs) significantly increased the amount of total dietary fiber and mineral matter of cookies. On the whole, the addition of SBPEs increased cookie hardness, but the hardness decreased with an increase in extrudate particle size. Sensory characteristics (except for the taste) were the most influenced by extrudate particle size.

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TiN/ZrO2 multilayers synthesized on GCr15 bearing steel using plasma immersion ion implantation and deposition

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2006.09.120 ◽

2007 ◽

Vol 201 (15) ◽

pp. 6615-6618 ◽

Cited By ~ 14

Author(s):

Tao Sun ◽

Langping Wang ◽

Yonghao Yu ◽

Yuhang Wang ◽

Xiaofeng Wang ◽

...

Keyword(s):

Ion Implantation ◽

Bearing Steel ◽

Gcr15 Bearing Steel ◽

Plasma Immersion Ion Implantation

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Microstructure and Grain Abrasion Properties of Cr3C2-NiCr Coating Prepared by Laser Cladding Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.271-272.3 ◽

2012 ◽

Vol 271-272 ◽

pp. 3-7

Author(s):

Long Wei ◽

Zong De Liu ◽

Xin Zhi Li ◽

Ming Ming Yuan ◽

Cheng Yuan Zhong

Keyword(s):

Wear Resistance ◽

Wear Rate ◽

Laser Cladding ◽

Micro Hardness ◽

High Quality ◽

Wear Resistant ◽

Hardness Tester ◽

Technology Analysis ◽

Main Component

Cr3C2-NiCr has high quality of wear resistant properties and is widely used in abrasive environment. In this paper, Cr3C2-NiCr coating was prepared on 45 steel by laser cladding technology. Analysis and research of the coatings were achieved by SEM and XRD to determine the main component and the different region on coatings. The hardness and the element component were investigated by micro-hardness tester and EDS. Abrasion tests were performed to contrast the wear resistance of two materials. The results indicate that the hardness of the coatings is nearly 3 times as the substrate. The coatings are well combined with the substrate and the phase of Cr3C2 has a large proportion in the coatings. Abrasion tests show that the average of wear rate on substrate is 5.2 times as the coatings.

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Effects of Flour Particle Size and Starch Damage on Processing and Quality of White Salted Noodles

Cereal Chemistry ◽

10.1094/cchem.2002.79.1.64 ◽

2002 ◽

Vol 79 (1) ◽

pp. 64-71 ◽

Cited By ~ 67

Author(s):

D. W. Hatcher ◽

M. J. Anderson ◽

R. G. Desjardins ◽

N. M. Edwards ◽

J. E. Dexter

Keyword(s):

Particle Size

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Performance, carcass traits and meat quality of lambs fed with different roughage:concentrate ratios associated with variable physically effective neutral detergent fibre content

The Journal of Agricultural Science ◽

10.1017/s0021859621000459 ◽

2021 ◽

pp. 1-11

Author(s):

L. de O. Queiroz ◽

A. M. Barbosa ◽

G. B. Mourão ◽

M. A. Fonseca ◽

L. F. B. Pinto ◽

...

Keyword(s):

Fatty Acids ◽

Particle Size ◽

Meat Quality ◽

Average Daily Gain ◽

Carcass Traits ◽

Faecal Excretion ◽

Neutral Detergent Fibre ◽

Fatty Acids Profile ◽

Colour Parameter

Abstract This study evaluated the effect of roughage:concentrate (R:C) ratio associated with a variable particle size of physically effective neutral detergent fibre (peNDF8) in the forage (Tifton-85 hay) on the performance, carcass traits and meat quality of lambs. Seventy-two 4-month-old, non-castrated Santa Ines male lambs (23.5 ± 2.32 kg BW) were distributed in a completely randomized design, in a 2 × 2 factorial arrangement [two peNDF8 hay particle sizes (13 and 6 mm) and two R:C ratios (700:300 and 500:500 g/kg DM total)]. DMI, DM, NFC and TDN digestibility's, N-intake and N-faecal excretion were affected by the R:C ratio (P < 0.05). However, the N-retained was not affected by the studied variables (P > 0.05). It was observed an interaction (P < 0.05) between the peNDF8 and R:C ratios for final BW, average daily gain (ADG), colour parameters and pH 24 h. The lower roughage ratio provided greater (P < 0.05) concentrations of C14:1, C16:1–cis9, C18:1–cis9, ΣMUFA, Σn–6:Σn–3 and hypocholesterolemic/hypercholesterolemic index, enzymatic activity Δ9desaturase-C16 and -C18. Lambs fed a lower roughage diet had improved performance and feed efficiency, however, presented reduced polyunsaturated fatty acids (PUFA) concentrations in the meat, especially Σn–3 family. Higher roughage diet and larger peNDF8 particle size improved the concentrations of PUFA while decreased Σn–6:Σn–3 ratio in meat. Larger peNDF8 particle size associated with higher roughage proportion, have reduced animal performance however, it increased protein concentration, a* and C* colour parameter without affecting fatty acids profile of Longissimus lumborum muscle.

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