Sinterable semi-crystalline powder and near-fully dense article formed therewith
US5342919A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 23, 1992 |
| Grant date | Aug 30, 1994 |
| Priority date | — |
| Expiry date | Nov 23, 2012 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2995/0094
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A laser-sinterable powder product has been prepared having unique properties which allow the powder to be sintered in a selective laser sintering (SLS) machine to form a sintered part which is near-fully dense. For most purposes, the sintered part is indistinguishable from another part having the same dimensions made by isotropically molding the powder. In addition to being freely flowable at a temperature near its softening temperature, the powder has a two-tier distribution in which substantially no primary particles has an average diameter greater than 180.mu.m, provided further that the number average ratio of particles smaller than 53.mu.m is greater than 80%, the remaining larger particles being in the size range from 53.mu.m to 180.mu.m. When the powder is a semicrystalline synthetic resin having a number average molecular weight in the range from about 30,000 to 500,000; a molecular weight distribution M.sub.w /M.sub.n in the range from 1 to 5; and, provides a window of sinterability in the temperature range from near the powder's softening temperature T.sub.s to its caking temperature T.sub.c, it is sintered layer-upon layer to form a near-fully dense part of arbitrary sha…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.