Quantitative surface fractography of alumina and alumina-SiC composites during diamond grinding

It has recently been shown that small additions of SiC to alumina can significantly improve both the surface finish for a given grinding treatment, and the resistance to severe wear. This paper describes experiments designed to obtain a clearer understanding of the mechanisms involved by correlating...

Full description

Bibliographic Details
Main Authors: Merino, J, Cock, A, Roberts, S, Todd, R
Format: Conference item
Published: 2005
_version_ 1826304281897074688
author Merino, J
Cock, A
Roberts, S
Todd, R
author_facet Merino, J
Cock, A
Roberts, S
Todd, R
author_sort Merino, J
collection OXFORD
description It has recently been shown that small additions of SiC to alumina can significantly improve both the surface finish for a given grinding treatment, and the resistance to severe wear. This paper describes experiments designed to obtain a clearer understanding of the mechanisms involved by correlating quantitative measurements of surface fracture during a standard abrasive wear test with the wear rate for a range of microstructures. The surface fracture parameters measured were (i) the proportion of the surface in which pieces of material had been removed by brittle fracture, and (ii) the size (equivalent circular diameter and depth) of the individual pullouts. Microstructures with systematic variations in grain size, SiC volume fraction, SiC particle size, SiC position (inter- or intra-granular) and sintering aids were tested. The results indicate that the reduction in wear rate on adding SiC or. reducing the grain size is caused by a reduction in the area fraction of surface pullout by brittle fracture. For low SiC contents (similar to 2vol%), this reduction in surface pullout is a consequence of the reduction in size of the individual pullouts. For higher SiC contents (10vol%), there is evidence that the nucleation of surface cracking is also inhibited. The underlying micromechanisms responsible for these effects are discussed.
first_indexed 2024-03-07T06:15:25Z
format Conference item
id oxford-uuid:f0ebe36c-9fa5-4c35-9e1b-6dafa5166c15
institution University of Oxford
last_indexed 2024-03-07T06:15:25Z
publishDate 2005
record_format dspace
spelling oxford-uuid:f0ebe36c-9fa5-4c35-9e1b-6dafa5166c152022-03-27T11:51:51ZQuantitative surface fractography of alumina and alumina-SiC composites during diamond grindingConference itemhttp://purl.org/coar/resource_type/c_5794uuid:f0ebe36c-9fa5-4c35-9e1b-6dafa5166c15Symplectic Elements at Oxford2005Merino, JCock, ARoberts, STodd, RIt has recently been shown that small additions of SiC to alumina can significantly improve both the surface finish for a given grinding treatment, and the resistance to severe wear. This paper describes experiments designed to obtain a clearer understanding of the mechanisms involved by correlating quantitative measurements of surface fracture during a standard abrasive wear test with the wear rate for a range of microstructures. The surface fracture parameters measured were (i) the proportion of the surface in which pieces of material had been removed by brittle fracture, and (ii) the size (equivalent circular diameter and depth) of the individual pullouts. Microstructures with systematic variations in grain size, SiC volume fraction, SiC particle size, SiC position (inter- or intra-granular) and sintering aids were tested. The results indicate that the reduction in wear rate on adding SiC or. reducing the grain size is caused by a reduction in the area fraction of surface pullout by brittle fracture. For low SiC contents (similar to 2vol%), this reduction in surface pullout is a consequence of the reduction in size of the individual pullouts. For higher SiC contents (10vol%), there is evidence that the nucleation of surface cracking is also inhibited. The underlying micromechanisms responsible for these effects are discussed.
spellingShingle Merino, J
Cock, A
Roberts, S
Todd, R
Quantitative surface fractography of alumina and alumina-SiC composites during diamond grinding
title Quantitative surface fractography of alumina and alumina-SiC composites during diamond grinding
title_full Quantitative surface fractography of alumina and alumina-SiC composites during diamond grinding
title_fullStr Quantitative surface fractography of alumina and alumina-SiC composites during diamond grinding
title_full_unstemmed Quantitative surface fractography of alumina and alumina-SiC composites during diamond grinding
title_short Quantitative surface fractography of alumina and alumina-SiC composites during diamond grinding
title_sort quantitative surface fractography of alumina and alumina sic composites during diamond grinding
work_keys_str_mv AT merinoj quantitativesurfacefractographyofaluminaandaluminasiccompositesduringdiamondgrinding
AT cocka quantitativesurfacefractographyofaluminaandaluminasiccompositesduringdiamondgrinding
AT robertss quantitativesurfacefractographyofaluminaandaluminasiccompositesduringdiamondgrinding
AT toddr quantitativesurfacefractographyofaluminaandaluminasiccompositesduringdiamondgrinding