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 binary system, tungsten-carbon. A tentative phase diagram is presented which differs significantly from the one proposed by Sykes in 1930 and which is generally accepted today. The data were obtained by high-temperature differential thermal analysis and classical quenching procedures, both supplemented by metallographic, x-ray, and chemical techniques.Results for the tungsten-carbon binary system indicate a eutectic between W and W2C at 2735°C, and a eutectic between W5C3 and C at 2765°C. The W2C lattice accommodates 72 and 74 atomic per cent W at 2475° and 2735°C, respectively. Carbon solubility is evident only at 2540°C, the eutectoid temperature. A new phase, W5C3, was discovered which is stable only above 2540°C. WC decomposes at 2730°C into W5C3 and C.

Date

1961

Index Abstract

Contrails and DTIC

Photo Quality

Incomplete

Report Number

WADD TR 60-143 Part II

Creator

Dolloff, R. T.

Sara, R. V.

Corporate Author

Research Laboratory of National Carbon Company Division of Union Carbide Corporation

Laboratory

Directorate of Materials and Processes

Extent

25

Identifier

AD0278009

AD0278009

Access Rights

OTS

Distribution Classification

1

Contract

AF 33(616)-6286

DoD Project

7350

DoD Task

None Given

DTIC Record Exists

Yes

Distribution Change Authority Correspondence

None

Report Availability

Full text available

Date Issued

1961-05

Abstract

The work here reported is the result of an investigation of phase equilibria in the binary system, tungsten-carbon. A tentative phase diagram is presented which differs significantly from the one proposed by Sykes in 1930 and which is generally accepted today. The data were obtained by high-temperature differential thermal analysis and classical quenching procedures, both supplemented by metallographic, x-ray, and chemical techniques.Results for the tungsten-carbon binary system indicate a eutectic between W and W2C at 2735°C, and a eutectic between W5C3 and C at 2765°C. The W2C lattice accommodates 72 and 74 atomic per cent W at 2475° and 2735°C, respectively. Carbon solubility is evident only at 2540°C, the eutectoid temperature. A new phase, W5C3, was discovered which is stable only above 2540°C. WC decomposes at 2730°C into W5C3 and C.

Provenance

IIT

IIT

Type

report

Format

1 online resource (v, 19 pages) : ill.

Subject

Alloys

Carbon

Carbon Alloys

Ceramic Materials

Eutectics

High Temperature

Refractory Materials

Solubility

Tungsten

Tungsten Alloys

Publisher

Wright-Patterson Air Force Base, OH : Aeronautical Systems Division, Air Force Systems Command, United States Air Force

Distribution Conflict

No