Bonding Mechanisms Research Papers - Academia.edu (original) (raw)
0 Followers
Recent papers in Bonding Mechanisms
The ceramic shells were fabricated with ceramic slurry containing alpaha and gamma alumina as filler materials and colloidal silica binder. The shell characteristics in terms of bending strength and thermal expansion were measured. The... more
The ceramic shells were fabricated with ceramic slurry containing alpaha and gamma alumina as filler materials and colloidal silica binder. The shell characteristics in terms of bending strength and thermal expansion were measured. The phase transformation from gamma to alpha alumina were observed with transmission electron microscopy (TEM) and selected area electron diffraction (SAED) patterns. The metal to mould reaction were revealed with optical microstructures and hardness distribution. The bonding mechanism in the alumina and colloidal silica binder system was due to formation siloxane bonds. The phase transition γ- → α-Al2O3 occurs in two phases, respectively in the temperature ranges of 600°C - 850°C cubic crystal structure and from 850°C - 1000°C, α-Al2O3 with corundum crystal structure. The cracks have been observed in the investment shells made of gamma alumina after 7075 Al-alloy pouring.
The characteristics dip-casting slurries judge the performance of investment casting process. The paper presents a hypothesis on the bonding mechanism in the ceramic shells developed from coal flyash. Experiments have been carried out to... more
The characteristics dip-casting slurries judge the performance of investment casting process. The paper presents a hypothesis on the bonding mechanism in the ceramic shells developed from coal flyash. Experiments have been carried out to study the effects of filler loading, aging and air-drying on the strength of shells. The results indicate substantial reduction in the sedimentation under operating conditions and enhancement in the shells strength.