Title

Silica Microbubbles

Date

1960

Index Abstract

Contrails and DTIC

Photo Quality

Not Needed

Report Number

WADD TR 60-899 Part 1

Corporate Author

Emerson & Cuming, Inc.

Laboratory

Materials Central

Extent

76

Identifier

AD0260982

AD0260982

Access Rights

OTS

Distribution Classification

1

Contract

AF 33(616)-5840

DoD Project

7340

DoD Task

73402

DTIC Record Exists

Yes

Distribution Change Authority Correspondence

None

Special Scanning Requirements

Fold out pages

Report Availability

Full text available

Full text available

Date Issued

1960-12

Abstract

Glass microbubbles 0.150 to 0.020 mm diameter, having a bulk density of 0.25 g/cc and a true density of 0.50 g/cc have been greatly improved by decreasing the alkali content and also by making them of vitreous silica. The improvements consist of marked decrease in moisture adsorption, enhanced electrical properties, and great increase in maximum use temperature. An acid leaching technique applied to the commercially available 18% alkali "Eccospheres" of Emerson & Cuming, Inc. reduces the alkali content to 6% and increases the maxim m use temperature from 500°C to 800°C. Formation from pure silica by a direct high temperature process to give a vitreous silica bubble retains the useful characteristics of the low-melting-alkali-glass bubble with the desirable properties of vitreous silica - low to negligible moisture adsorption, outstanding dielectric properties even at high temperature, and a safe use temperature for most applications of 1300°C. The feasibility of the direct process has been briefly demonstrated on pilot plant scale at 2 lb/hr rate.

Work on bonding the high temperature product into structural shapes is described.

Publisher

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

Distribution Conflict

No

Provenance

IIT

Type

report

Subject

Physical Properties

Glass

Silicates

Silicon Compounds

Boron Compounds

Bubbles

Dielectric Properties

Dioxides

Insulation

Materials

Preparation

Production

Sodium Compounds

Spheres

Thermal Insulation

Format

1 online resource

Creator

Lefforge, J. W.