Effect of gel time of 3D sand printing binder system on quality of sand mold/core

The development of microsystems and related products has caused an upsurge in the mass production of micro components. In the paper, fabrication of zirconia micro gears of 700μm, 800μm, 900μm based on water-soluble binder were investigated. The water-soluble binder system consists of 30%PEG-4000+10%SA+30%PVB+30%EVA components. Experimental results show that zirconia micro gears are successfully fabricated using the in-house feedstock. And the decrease of the molecular weight of water-soluble component is beneficial to the quality of the molded part.

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Effect of Different Gating Systems and Sand Mold Binder on the Cast-Quality of Bicycle Frame Produced through Sand Casting Method

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.402.100 ◽

2020 ◽

Vol 402 ◽

pp. 100-107

Author(s):

Akhyar ◽

Husaini ◽

Masri Ali ◽

Nurdin Ali ◽

Farhan Ahmad

Keyword(s):

Water Glass ◽

Casting Process ◽

Sand Mold ◽

Casting Defects ◽

Casting Method ◽

Mold Casting ◽

Furan Resin ◽

Bicycle Frame ◽

The Impact

The bicycle frame produced through the metal casting process by recycling aluminum alloys can be an environmentally friendly alternative solution. Mold types and gating systems used generally affects the quality of the casting product. In this experiment, the effect of gating number and riser type variations (for sand binder) observed on casting defects, hardness, and impact value. Subsequently, chemical composition and microstructure of recycled aluminum metal from bicycle frames produced through sand mold casting are also evaluated. Three types of risers are bentonite, water glass, and furan resin. The results indicate that mold with two gating system has a low porosity as casting defects. The cast-bike frame produced using furan resin reaches the highest hardness value of 46 HRB compared to water glass and bentonite as the binder of sand-molds. The impact test observes 3.9 J carried out by the ASTM E23 sample at room temperature.

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Effects of alumina precursor species in a ternary-phase binder system on the strength of sand mold

Ceramics International ◽

10.1016/j.ceramint.2017.10.179 ◽

2018 ◽

Vol 44 (2) ◽

pp. 2223-2230 ◽

Cited By ~ 2

Author(s):

Yeon-Gil Jung ◽

Erdenechuluun Tumenbayar ◽

Hyeun-Hee Choi ◽

Hye-Young Park ◽

Eun-Hee Kim ◽

...

Keyword(s):

Ternary Phase ◽

Sand Mold ◽

Binder System

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Evaluation of nano ceramic coating on radiographic defects of thin-walled AL4-4 aluminum alloy sand casting

Metallurgical and Materials Engineering ◽

10.30544/212 ◽

2016 ◽

Vol 22 (3) ◽

pp. 193-204

Author(s):

Mansour Borouni ◽

Behzad Niroumand ◽

Mohammad Hossein Fathi

Keyword(s):

Transfer Rate ◽

Ceramic Coating ◽

Maximum Amount ◽

Sand Mold ◽

Gravity Casting ◽

X Ray ◽

Ceramic Nanoparticles ◽

Shrinkage Defects ◽

Thin Walled

Internal defects are among the problems in gravity casting of aluminum parts. The main internal volumetric defects are gas and shrinkage defects which form during solidification of the melt and drastically reduce the quality of the produced parts. These defects adversely affect the mechanical properties of thin walled castings parts. In this study, ceramic nanoparticles coatings were applied on the sand mold and the effect of mold coatings on the reduction of defects were investigated. X-ray radiography was used to detect defects in sand molds with ceramic nanoparticles coatings. For comparison, this test was performed on molds with micro-ceramic and graffiti coatings and uncoated sand mold. The results showed that the maximum amount of gas and shrinkage defects was observed in casting parts from AL4-1 alloy in uncoated molds. On the other hand, the minimum defects were found in molds coated with ceramic nanoparticles. It seems that the reduced defects in casting parts in molds coated with ceramic nanoparticles may be due to high thermal and chemical stability and higher heat transfer rate of the coating. These results can facilitate the production of high quality aluminum alloys parts using nanotechnology.

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Study on Preparation of Mesoporous Silica Aerogels with Low Density and High Properties via Ambient Pressure Drying

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.1491 ◽

2010 ◽

Vol 148-149 ◽

pp. 1491-1496

Author(s):

Gang Qiang Geng ◽

Wei Tao Bi ◽

Yu Zhang ◽

Deng Ke Sun

Keyword(s):

Mesoporous Silica ◽

Ambient Pressure ◽

Sol Gel ◽

Silica Aerogels ◽

Ambient Pressure Drying ◽

Ethanol Solution ◽

Low Density ◽

Micro Structure ◽

Gel Time

The SiO2 aerogels of low density was fabricated by ion exchange and sol-gel method on the basis of sodium silicate. The effect of pH, aging，addition of DCCA and annealed temperature on the gel time, aerogel density, porosity and the micro-structure was systemly studied. The results showed that when the pH is 5, aging was 30%Vol .of TEOS/ethanol solution ,the addition of DCCA was 1.5ml, the gel system was annealed at 50 for 84 h, 60 for 72h, the best quality of silica aerogels with low density (0.14g/cm3), higher specific surface(610.643 m2/g) and pore size of 20~40 nm can be obtained.

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Effect of Pattern-Less Forming Process on Quality of Sand Mold Surface

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1001.115 ◽

2020 ◽

Vol 1001 ◽

pp. 115-120

Author(s):

Li Jun Guo ◽

Zhong De Shan ◽

Er Biao Jiang

Keyword(s):

Surface Quality ◽

Great Influence ◽

Sand Mold ◽

Extrusion Force ◽

Mold Surface ◽

Object Surface ◽

Forming Process ◽

Abrasive Resistance ◽

Sand Material

The pattern-less sand mold was used as the research object, surface quality of sand mold was carried out by using surface abrasion tester. In this paper, the influence of sand material such as the types of sand, resin contents and extrusion pressure on the surface quality was studied through the single-factor test. The results showed that: different sand mold had different surface abrasive resistance. The angle coefficient of sand has a great influence on the surface abrasive resistance of the sand mold. With the increase of extrusion force, the surface abrasive resistance of sand mold increased. And as the resin content increased, the surface abrasive resistance of sand mold continued to increase.

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Research on the Content of Binder in Pattenless Casting Manufacturing Technique

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.458.206 ◽

2010 ◽

Vol 458 ◽

pp. 206-211 ◽

Cited By ~ 2

Author(s):

Wei Dong Yang ◽

L.B. Liu

Keyword(s):

Layer Thickness ◽

Process Parameters ◽

Theoretical Basis ◽

Scanning Speed ◽

Resin Content ◽

Sand Mold ◽

Curing Agent ◽

Manufacturing Technique ◽

Sand Particles

The patternless casting manufacturing (PCM) technique adopted two nozzles to spray the binder and the curing agent separately into the dry sand under the control of a computer. In the PCM technique, the resin content of sand mold is mostly determined the quality of the final casts. In this paper the content of the binder droplets in sand particles is analyzed in detail. Thus it provides the theoretical basis for these process parameters such as scanning speed, layer thickness and so on. The results of experiments well verify the analysis.

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