Accession Number:

ADA067778

Title:

Study of Erosion Mechanisms of Engineering Ceramics.

Descriptive Note:

Interim technical rept. no. 7,

Corporate Author:

SOLAR TURBINES INTERNATIONAL SAN DIEGO CA

Personal Author(s):

• Gulden,Mary Ellen

Report Date:

1979-03-01

Pagination or Media Count:

24.0

Abstract:

A MgF2 target was subjected to impact conditions from single particle to 10 to the 10th power impacts which simulated a natural dust environment quartz particles in the subsonic velocity regime. The function of particle size and velocity predicted by the elastic-plastic impact model is followed for this system. Impact damage is characterized by a heavily deformed contact area between particle and target, with radial cracks propagating outward from the contact zone, and with subsurface lateral cracks propagating outward on planes nearly parallel to the surface. The laterally cracked material is responsible for most of the erosion loss. This type of damage is also consistent with the elastic-plastic model. For a given particle size - velocity condition the volume of material removed for a single impact can vary over three orders of magnitude. This large variation is due primarily to differences in particle orientations during impact which results from the irregular natural quartz particles. For these conditions there is not a significant difference between the amount of material removed for the first impact and for subsequent impacts on the damage area of the initial impact. The results imply that there is not an incubation period or damage enhancement effect for erosion in the elastic-plastic impact response regime. Author

Descriptors:

• *CERAMIC MATERIALS
• *EROSION
• *MAGNESIUM COMPOUNDS
• *FLUORIDES
• *EROSION RESISTANCE
• VELOCITY
• PARTICLE SIZE
• IMPACT
• DAMAGE
• ORIENTATION(DIRECTION)
• DUST
• QUARTZ
• PARTICLES
• INFRARED WINDOWS

Subject Categories:

• Ceramics, Refractories and Glass

Distribution Statement:

APPROVED FOR PUBLIC RELEASE