抄録
Purpose : A new device was made that can produce a high-speed jet of either water (water jet) or abrasives mixed with water (abrasive jet). This paper reports on the ability of this device to remove investment and metal oxides from cast alloy surfaces.
Materials and Methods : Two gypsum blocks, three investment blocks before and after heating, and three cast metal plates were tested with the newly produced device. The pressure of the jet was 4 or 8 MPa, and two types of abrasives (#400 and #1500 SiC and glass beads) were used. After treatment, the surface quality was observed with a charge coupled device camera. The concave depths of the investments were measured with a laser displacement meter and the alloy surfaces evaluated with a surface texture measuring apparatus. The concave depths of the investments and the surface roughness (Ra) were statistically analyzed with two-way ANOVA and Tukey's test using data from ten points.
Results : After heating, the investment was removed by a 4 MPa water jet ; the concave depth of the investments was from 0.7 to 8.2 mm. The gypsum was removed by the abrasive jet. The oxide films were removed by the 4 MPa abrasive jet using the abrasive agents.
Conclusion : This study examined the potential use of a new laboratory tool. It demonstrated that a water jet could remove investment after heating. Gypsum, adhered investment, and metal oxide were removed with an abrasive jet. This new device can be used effectively as a laboratory tool for removal of unwanted surface materials.
