Browse Prior Art Database

Method of Producing Mono-Dispensed Spherical Solids

IP.com Disclosure Number: IPCOM000038464D
Original Publication Date: 1987-Jan-01
Included in the Prior Art Database: 2005-Jan-31
Document File: 3 page(s) / 38K

Publishing Venue

IBM

Related People

Walker, GF: AUTHOR [+2]

Abstract

This is a means of producing homogenous, spherical particles of glass, ceramics and metals with predetermined compositions. With additional automated processes we are able to produce mono-dispersed spherical solids, in micron and submicron ranges. The mono-dispensed, homogenous compositional spherical particles have wide range applications, such as, multilayer ceramic substrates and magnetic disks for storage, etc. The monodispersed spherical particles will result in high packing density in sintered ceramics. High packing density, low porosity, and small flow size are essential for high strength ceramics. The uniform fine microstructure also allows much higher circuit integration density for electronic applications.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Page 1 of 3

Method of Producing Mono-Dispensed Spherical Solids

This is a means of producing homogenous, spherical particles of glass, ceramics and metals with predetermined compositions. With additional automated processes we are able to produce mono-dispersed spherical solids, in micron and submicron ranges. The mono-dispensed, homogenous compositional spherical particles have wide range applications, such as, multilayer ceramic substrates and magnetic disks for storage, etc. The monodispersed spherical particles will result in high packing density in sintered ceramics. High packing density, low porosity, and small flow size are essential for high strength ceramics. The uniform fine microstructure also allows much higher circuit integration density for electronic applications. The mono-dispersed, spherical spacer in magnetic discs (Al2O3) will not scratch the thin film heads, increasing the reliability of the head-disk assembly. Currently, there are ways of making spherical particles, such as precipitation from solutions and chemical vapor deposition. The processes are expensive and difficult to control, especially the composition. The types of particles produced are limited. It is also difficult to produce large quanities for manufacturing use. This method of producing mono- dispersed spherical particles is simple, economical and easy to implement in manufacturing large quantities. It allows wider ranges of the types of ceramics, glass-ceramics and metals produced. The composition of the particles can be controlled tightly. The manufacturing system is shown in the drawing. The conventional irregularly shaped non-mono-dispersed particles feed into powder feeder 31 which is equipped with supply hopper 4. The hopper 4 is designed to minimize agglomeration of the particles which are fed. Gases, such as hydrogen 1, argon 2 or others, are supplied by pipe 30, and the particles are fed by powder feeder 31 into a plasma gun 6. The gun 6 is energized by a high voltage discharge to produce a plasma. The powders are discharged and sprayed into a catch vessel 8. The work distance between the gun 6 and vessel 8 is about 12" - 15". The catch vessel 8 is filled via line 32 from solvent supply 13 with a solvent, such as distilled water, as a bath to catch the spherical particles. The solvent level is controlled by the solvent supply 13 and the solvent feeder valve 9. The solvent-particle mixture is pumped from catch vessel 10 into a mixture control unit...