Title

Research Study To Determine The Phase Equilibrium Relations Of Selected Metal Carbides At High Temperatures

Description

The work here reported is the result of an investigation of phase equilibria in the ternary system, silicon-boron-carbon. Techniques for extending the high temperature range of measurements have been developed. Accurate phase diagrams for the silicon-carbon and the boron-carbon binaries have been obtained and details of the ternary system have been determined in the high carbon content region. The data were obtained by high temperature differential thermal analysis and by photoelectric thermal analysis, both supplemented by metallographic, X-ray and chemical techniques.Results for the boron-carbon binary system indicate that boron melts at 2130 ± 10°C and that B4C has a congruent melting point of 2470 ± 20°C. Boron and B4C form a eutectic at 2080 ± 20°C, whereas carbon and B4C form a eutectic at 2390 ± 20°C.Results for the silicon-carbon binary indicate a eutectic between silicon and SiC at 1402 ± 5°C. SiC melts incongruently at 2540 ± 40°C. The peritectic point is located at 27 per cent carbon. Results for the ternary system indicate a eutectic between B4C, SiC and carbon at 2250 ± 20°C. No compound formation has been observed in the high carbon region of the ternary system.

Date

1960

Index Abstract

Contrails only

Photo Quality

Incomplete

Report Number

WADD TR 60-143

Corporate Author

Research Laboratory of National Carbon Company Division of Union Carbide Corporation

Laboratory

Materials Central

Extent

28

PB Number

PB171365

NTRL Accession Number

AD244270

Identifier

AD0244270

AD0244270

Access Rights

OTS

Distribution Classification

1

Contract

AF 33(616)-6286

DoD Project

7350

DoD Task

73500

DTIC Record Exists

Yes

Distribution Change Authority Correspondence

PER AFWAL LTR

Report Availability

Full text available

Date Issued

1960-07

Abstract

The work here reported is the result of an investigation of phase equilibria in the ternary system, silicon-boron-carbon. Techniques for extending the high temperature range of measurements have been developed. Accurate phase diagrams for the silicon-carbon and the boron-carbon binaries have been obtained and details of the ternary system have been determined in the high carbon content region. The data were obtained by high temperature differential thermal analysis and by photoelectric thermal analysis, both supplemented by metallographic, X-ray and chemical techniques.Results for the boron-carbon binary system indicate that boron melts at 2130 ± 10°C and that B4C has a congruent melting point of 2470 ± 20°C. Boron and B4C form a eutectic at 2080 ± 20°C, whereas carbon and B4C form a eutectic at 2390 ± 20°C. Results for the silicon-carbon binary indicate a eutectic between silicon and SiC at 1402 ± 5°C. SiC melts incongruently at 2540 ± 40°C. The peritectic point is located at 27 per cent carbon. Results for the ternary system indicate a eutectic between B4C, SiC and carbon at 2250 ± 20°C. No compound formation has been observed in the high carbon region of the ternary system.

Provenance

IIT

Type

report

Format

1 online resource (v, 22 pages) : ill.

Subject

Boron Compounds

Carbides

Ceramic Materials

Eutectics

Melting

Phase Studies

Silicon Compounds

X Ray Spectroscopy

Publisher

Wright-Patterson Air Force Base, OH : Wright Air Development Division, Air Research and Development Command, United States Air Force

Distribution Conflict

No

Creator

Dolloff, R. T.