Film-forming material and film
A coating material containing an oxyfluoride of yttrium and having a Fisher diameter of 1.0 to 10 μm and a tap density TD to apparent density AD ratio, TD/AD, of 1.6 to 3.5. The coating material preferably has a pore volume of pores with a diameter of 100 μm or smaller of 1.0 cm 3 /g or less as measured by mercury intrusion porosimetry. A coating containing an oxyfluoride of yttrium and having a Vickers hardness of 200 HV0.01 or higher. The coating preferably has a fracture toughness of 1.0×10 2 Pa·m 1/2 or higher.
1. A coating comprising an oxyfluoride of yttrium, the coating having a Vickers hardness od 200 HV0.01 or higher, the coating having not greater than ten projections per 1.0 cm×1.0 cm area thereof,
wherein each of the projections has at least one width dimension of at least 5 μm, and
the width dimension is measured in a direction parallel to a surface of the coating wherein the coating is an ion plated coating.
2. The coating according to claim 1 , having a fracture toughness of 1.0×10 2 Pa·m 1/2 or higher.
3. The coating according to claim 2 , having a thickness of 3 μm or larger.
4. The coating according to claim 2 , having not greater than eight of the projections per 1.0 cm×1.0 cm area thereof.
5. The coating according to claim 2 , having not greater than four of the projections per 1.0 cm×1.0 cm area thereof.
6. The coating according to claim 2 , having not greater than two of the projections per 1.0 cm×1.0 cm area thereof.
7. The coating according to claim 1 , having a thickness of 3 μm or larger.
8. The coating according to claim 1 , having not greater than eight of the projections per 1.0 cm×1.0 cm area thereof.
9. The coating according to claim 1 , having not greater than four of the projections per 1.0 cm×1.0 cm area thereof.
10. The coating according to claim 1 , having not greater than two of the projections per 1.0 cm×1.0 cm area thereof.