Research on Performance of Foundry Sand under the Effect of Chemical Binder

2014 ◽  
Vol 597 ◽  
pp. 262-265
Author(s):  
Qing Zhou Sun ◽  
Jing Guang Yan ◽  
Pu Qing Zhang ◽  
Zhong Kui Zhao ◽  
Hang Du

This paper makes an experiental research on the performance of foundry sand under the effect of chemical binder. It discoveries the raw sand with different origin will have different properties even though they have the same particle size. The properties of their molding sand are also obviously different. For the raw sand that in the same particle size with similar acid demand value and four-screen distribution, the better grain shape will earn them a higher molding sand strength even though they have higher clay content. Under the effect of liquid binder, compared to the molding sand mixed from the sand of three-screen distribution, the molding sand mixed from those of four-screen distribution sand with other properties similar will have a higher tensile strength While under the effect of solid phenolic resin adhesive, the three-screen sand with good grain shape will have a high sand strength.

2014 ◽  
Vol 1073-1076 ◽  
pp. 43-46
Author(s):  
Hao Zhang ◽  
Xiao Chun Li ◽  
Ming Zhu ◽  
Liang Hong ◽  
Gao Li Chu

In this study, the tensile strength of phenolic resin adhesive was reinforced by the use of surface-modified nanocrystalline cellulose (NCC). The original NCC was modified by 3-methacryloxy-propyltrimethoxysilane (MPS) to improve the wetting property with the phenolic resin adhesive. The phenolic resin adhesive with surface-modified NCC was analyzed by Fourier transform infrared (FT-IR). Tensile strength of the modified phenolic resin adhesive was tested according to Chinese National Standard GB/T 2567-2008. The results showed that the wetting property between NCC modified by MPS and phenolic resin adhesive was increased by 21.7% and the tensile strength of phenolic resin adhesive with modified NCC was enhanced from 6.25 MPa to 15.97 MPa.


2010 ◽  
Vol 97-101 ◽  
pp. 1037-1040 ◽  
Author(s):  
Qing Zhou Sun ◽  
Rong Fu Xu ◽  
Zhong Kui Zhao ◽  
Pu Qing Zhang

The green sand containing hot-box resin sand was reclaimed by the process of calcination followed by mechanical reclamation. The reclaimed sands were reused in the hot-box process. The grain size distribution, the shape factor, the clay content and the acid demand value were determined. The results show that the acid demand value of the reclaimed sand is higher than that of the base sand. Compared with the base sand, the grain size of the reclaimed sand is almost no difference. It can also be observed that the tensile strength of the molding sand is influenced by the acid demand value and clay content, but the reclaimed sand can still meet the casting process needs. In addition, the reclaimed green sand is satisfactory for hot-box process.


1944 ◽  
Vol 17 (2) ◽  
pp. 451-474
Author(s):  
D. Parkinson

Abstract Carbon blacks can be grouped into different classes according to the way in which their fineness of division relates to different properties in rubber. Within any one class the principal properties vary in a regular manner with particle size. The normal class consists of the furnace carbons, Kosmos (Dixie)-40, Statex, the rubber-grade impingement carbons, and possibly, the color-grade impingement carbons. The subnormal classes consist of thermal carbons and acetylene and lamp blacks. Irrespective of the above classification, the properties which depend more on fineness of division than on other factors are rebound resilience, abrasion resistance, tensile strength and tear resistance. The lower limit of particle diameter for best tensile strength and tear resistance appears to be higher than that for abrasion resistance. B.S.I, hardness and electrical conductivity are properties which depend at least as much on other factors as on particle size. Stiffness (modulus) depends more on other factors than on particle size. Factors modifying the effects of particle size (or specific surface) include the presence of carbon-carbon structures and a reduction in strength of bond in rubber-carbon structures. Carbon black is thought to exist in rubber in four states: agglomerated, flocculated, dispersed, and bonded to the rubber molecules (the reënforcing fraction). Abrasion resistance is regarded as providing the only reliable measure of reënforcement.


2017 ◽  
Vol 140 (3) ◽  
Author(s):  
Thella Babu Rao

One of the major advantages of metal matrix composites (MMCs) is that their tailorable properties meet the specific requirements of a particular application. This paper deals with the experimental investigations done on the effects of the reinforcement particulate size and content on the Al7075/SiC composite. The composites were manufactured using stir casting technique. The effect of SiC particle size (25, 50, and 75 μm) and particulate content (5, 10, and 15 wt %) on the microstructural, mechanical properties, and wear rate of the composites was studied and the results were analyzed for varied conditions of reinforcement. Scanning electron microscope (SEM) examinations were used to assess the dispersion of SiC particles reinforced into the matrix alloy and was found with reasonably uniform with minimal particle agglomerations and with good interfacial bonding between the particles and matrix material. X-ray diffraction (XRD) analysis confirmed the presence of Al and SiC with the composite. The results of mechanical tests showed that the increasing SiC particle size and content considerably enhanced the ultimate tensile strength and hardness of the composites while the ductility at this condition was decreased. The highest ultimate tensile strength of 310 MPa and hardness of 126 BHN were observed for the composites containing 15 wt %. SiC at 75 μm. Lesser the wear resistance of the reference alloy while it was enhanced up to 40% with the composites. The wear resistance was increased up to 1200 m of sliding distance for all the composites, whereas for the composite containing 75 μm SiC particles, it was extended up to 1800 m.


Author(s):  
Jeongki Lee ◽  
Dante Fratta ◽  
Idil Deniz Akin

We developed an experimental program to monitor how interparticle forces control fine-grained soils' mechanical behavior when saturation changes from the tightly adsorbed regime to saturation. The testing program uses stiffness (i.e., S-wave velocity) and strength (i.e., Brazilian tensile strength) tests on kaolinite, silica flour, and diatomaceous earth soil samples at very low confining stresses (< 5 kPa). Three fine-grained soils yield a range of different properties, including particle size, specific surface area, negative charge density, and internal/external particle porosity. Results show that shear stiffness and tensile strength follow similar trends, emphasizing that the same interparticle forces control the mechanical responses. In particular, the interpretation of S-wave velocity measurements shows three different behavior ranges: a van der Waals attraction range, a capillary-dominated interparticle forces range, and the continuous decrease in the capillary forces from the saturation at the air-entry pressure until full saturation. We show that the interparticle forces respond to a complex function of water content, particle size, particle separations, surface charge density, and the presence of internal particle porosity.


2021 ◽  
Vol 25 (Special) ◽  
pp. 2-72-2-77
Author(s):  
Hassanein M. Nhoo ◽  
◽  
Raad. M. Fenjan ◽  
Ahmed A. Ayash ◽  
◽  
...  

The current paper deals with investigating the effect of two different fillers on the thermal and mechanical characteristics of epoxy-based composite. The filler used throughout the study are: charcoal and Pyrex, both of them are different in nature and have not been investigated thoroughly or even compared fairly in terms of their effect on polymer matrix. Further, they can be considered as a cheap filler, charcoal can be obtained from a simple pyrolysis process of plants (charcoal) and Pyrex waste can be collected easily. Both types are added to the selected matrix with volume percent ranged from 10 to 60 with increments of 10. To ensure a fair comparison, the particle size is fixed (is about 1.7 micrometer). The results showed that the epoxy thermal conductivity has enhanced by about two orders of magnitudes over the studied range of filler. In terms of mechanical properties, the charcoal improves the tensile strength about 84% at 60% volume fraction while the Pyrex effect is about 40% at the same filler level. On the contrast, the results of compressive strength do not show an appreciable improvement overall. It decreases by about 12% at 60% volume fraction of charcoal while increases about the same percent with Pyrex at the same filler level.


Author(s):  
F Hakami ◽  
A Pramanik ◽  
AK Basak ◽  
N Ridgway ◽  
MN Islam

Effect of abrasive particle size on tribological behaviour of different elastomers was investigated experimentally in this study. The size of abrasive particle size was varied from coarse (425 µm) to fine (82 µm). Wear rate and coefficient of friction were calculated and analyzed accordingly followed by the examination of worn surfaces by a scanning electron microscope to unravel the wear mechanism. Experimental results showed that abrasive size had a significant effect on wear and friction behaviour of the elastomers. As the abrasive particle size increased, wear rate and coefficient of friction also increased at different rates and exhibited different wear mechanisms that changed from friction to fatigue and roll formation. Mechanical properties of elastomers such as hardness, tensile strength, tear strength, and elongation at break also contributed to wear and friction. The effect of elongation at break and tensile strength on wear rate is more pronounced at lower abrasive particle size, whereas hardness and tear strength play a pivotal role at the higher abrasive size.


2020 ◽  
Vol 262 ◽  
pp. 114762
Author(s):  
Lai Peng Lim ◽  
Joon Ching Juan ◽  
Nay Ming Huang ◽  
Leng Kian Goh ◽  
Fook Peng Leng ◽  
...  

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