奈米碳酸鈣添加劑對背漿及陶殼模性能的影響

Effects of Nano-precipitated Calcium Carbonate Additive on the Properties of Backup Slurry and Ceramic Shell Mold

高家豪(C.H.Kao) ； 林祐任(Y.R.Lin) ； 楊國和(Koho Yang)

《鑄造工程學刊》 35卷1期 (2009/03) Pp. 1-8

https://doi.org/10.29809/JTFS.200903.0001

摘要

本文主要在探討奈米碳酸鈣添加於精密鑄造陶殼模背漿中對泥漿及陶殼模性能所產生的影響。採用五層半陶殼模（兩層面漿，三層半背漿），面漿主要成份為鋯粉與矽膠液（以3.8:1比例混合），背漿則為馬來粉與矽膠液（以2:1比例混合）。
添加於背漿對漿體的影響主要是針對泥漿流變性，pH值，泥漿溫度所產生的變化進行量測，對陶殼模性能的影響則是針對陶殼模濕態，高溫，殘留破斷強度及高溫透氣度進行量測。泥漿流變性是採用流變儀與詹氏杯來量測，兩者所得到的數據可以相互對應與驗證。
實驗結果顯示：泥漿添加奈米碳酸鈣具有防沈降的作用，添加12wt%奈米碳酸鈣泥漿靜置到完全沈降所需時間比未添加奈米碳酸鈣之泥漿延長4倍。添加奈米碳酸鈣於背漿會延長背漿的壽命和改變泥漿流變性（泥漿黏度降低），使得在預混的過程中能在短時間內達到所需的泥漿黏度值，縮短泥漿混拌所需的時間，添加12wt%奈米碳酸鈣時效果最為明顯。而添加劑也會對陶殼模破斷強度與高溫透氣度造成不同的影響，以添加6wt%奈米碳酸鈣時所得到的綜合效果較佳。

關鍵字

精密鑄造 ； 泥漿 ； 奈米碳酸鈣 ； 破斷強度

並列摘要

The effects of the nano-precipitated calcium carbonate additives on the properties of backup slurry and ceramic shell mold of the investment casting have been studied. The ceramic shell mold consisted of five and a half layers (two layers for primary slurry, three and a half layers for backup slurry). The materials used for primary slurry were zircon flour and water based colloidal silica (mix ratio was 3.8:1), and for backup slurry were molochite and colloidal silica (mix ratio was 2:1).
The main effects of the additive on the slurry were the measurement of the variations occurred by the rheology, pH and temperature. The effects on the ceramic shell mold were the measurement of the MOR (green strength, hot strength and fired strength) and high temperature permeability. The rheology of the slurry was measured by the rheometer and the Zahn cup, respectively. The data obtained were double checked.

並列關鍵字

Investment casting ； Slurry ； Nano-precipitataed calcium carbonate ； Modulus of rupture MOR