Polyalkylene glycol-grafted polycarboxylate suspension and dispersing agent for cutting fluids and slurries
Cutting fluids for brittle materials, e.g., silicon ingot, comprise, in weight percent: A. 70-99% polyalkylene glycol (PAG), e.g., polyethylene glycol; B. 0.01-10% PAG-grafted polycarboxylate; and C. 0-30% water. These cutting fluids are used with abrasive materials, e.g., silicon carbide (SiC), to form cutting slurries. The slurry is sprayed on the cutting tool, e.g., a wire saw, to cut a brittle work piece, e.g., a silicon ingot.
1. A cutting slurry comprising in weight percent:
A. 28-67% PAG;
B. 0.05-3.35% PAG-g-polycarboxylate;
C. 0-10% water; and
D. 33-60% abrasive material.
2. The cutting slurry of claim 1 in which the PAG is PEG and the PAG-g-polycarboxylate is PEG-g-polycarboxylate.
3. The cutting slurry of claim 2 in which the abrasive material is silicon carbide (SiC).
4. The cutting slurry of claim 3 in which water is present.
5. A method of cutting a brittle material with a cutting wire, the method comprising the step of applying abrasive slurry to the wire as the brittle material is brought into contact with the wire, the abrasive slurry comprising:
A. 28-67% PAG;
B. 0.05-3.35% PAG-g-polycarboxylate;
C. 0-10% water; and
D. 33-60% abrasive material.
6. The method of claim 5 in which the PAG is PEG and the PAG-g-polycarboxylate is PEG-g-polycarboxylate.
7. The method of claim 6 in which the abrasive material is SiC.
8. The method of claim 7 in which water is present.