# Re: DTM RapidTool

From: Christian Nelson (nelsonc@dtm-corp.com)
Date: Tue Jun 23 1998 - 02:04:20 EEST

Matt,

I would like to provide some information about the brown parts made
with the new RapidSteel 2.0 material. This material was introduced
last month at the RP&M show in Dearborn, MI. It will be commercially
available at the end of the summer.

The metal powder is a 316 Stainless steel. The particle size range is
22 to 53 microns. The volume average particle size of 34 microns.
The pore size is typically 1/7 the diameter of the particles (i.e.
34/7 = 4.9 microns). The brown part has a relative density of 60%.

DTM has not measured the mechanical properties or surface finish of
the brown part. These parts can be finished, therefore a smooth
surface can be achieved. If you would like to test the mechanical
properties and share that information with the rp-ml, I can provide
samples.

The dimensional change during burnout/sintering is less than 0.5%.
This is a global shrinkage (the part shrinkage is uniform). This
value is calculated by measuring the green and brown parts then
plotting the difference versus the nominal dimension. The slope of
the curve is the shrinkage.

The cost per unit volume of brown part is \$280/liter. (1 liter = 100 mm
cube = 61 cubic inches).

Christian Nelson
Product Marketing Manager
DTM Corporation

Subject: DTM RapidTool
Author: "Murphy, Matt" <matt_murphy@peragroup.com> at dtm-corp
Date: 6/22/98 6:25 AM

Dear List,

Could any practitioners of the SLS RapidTool process answer the following:

Mechanical properties of the brown part
Pore size and structure of the brown part
Surface finish of brown part
Dimensional change on burnout/sintering when moving from green to brown part
(is it a global figure or geometry dependant? How is the figure
calculated?)
Rough cost per unit volume of brown part (ie cost to build a 100mm cube)
Particle size of metal powder (what options are available)
What is the metal powder (what options are available)
What is the binder

Answers to any of these questions would be greatly appreciated.

Matt

****************************************************************************
*************
Dr Matt Murphy
Head of Practice - Rapid Manufacturing
Pera Group
Melton Mowbray
Leicestershire
LE13 0PB
UK

Tel: 44 (0) 1664 501 501
Fax: 44 (0) 1664 501 589

email: matt_murphy@peragroup.com