Joseph A Grohowski

US Patent:

7326274, Feb 5, 2008

Filed:

Oct 17, 2002

Appl. No.:

10/272798

Inventors:

Joseph A. Grohowski - Glens Falls NY, US

Assignee:

Praxis Powder Technology, Inc. - Queensbury NY

International Classification:

B22F 1/00
C01M 125/04
C01M 107/04
C01M 107/34

US Classification:

75252, 508150, 508579, 508591

Abstract:

Multiphase polymeric binders for binder assisted forming of sinterable powder bodies are formulated to demonstrate improved rheological properties in the form of newtonion or near newtonion flow behavior thereby reducing dependence of binder viscosity on shear by tailoring the molecular weight and molecular weight distribution of the polymeric binder phases and the resulting polymer admixtures of the invention demonstrate shear rate independent behavior. Reduction of interfacial tension between binder phases by introduction of at least one macromolecule with separate segments selected to be compatible with the individual phases of the binder further increases processing performance as does use of polymer macromolecules having attributes that allow them to act as surface active materials at the interface of the sinterable powder and the multiphase binder composition. Predispersion of the surface active materials in the powder is facilitated by emulsification thereof in water prior to admixture with the powder.

US Patent:

20060002810, Jan 5, 2006

Filed:

Jul 2, 2004

Appl. No.:

10/884444

Inventors:

Joseph Grohowski - Glens Falls NY, US

International Classification:

B22F 3/11

US Classification:

419002000

Abstract:

A porous metal article having a predetermined pore structure. The porosity is provided by the use of an extractable particulate in a powder forming route to create a desired porosity. Extraction of the pore forming particulate prior to sintering of the powder minimizes contamination of the sintered article and allows for the processing of material sensitive to contamination such as titanium. Added functionality can be gained by co-forming the porous material with non-porous material to create an article with layers of differing characteristics. The article is suitable for use as an implant body is porous enough to facilitate tissue in-growth and bony fusion.

US Patent:

56419201, Jun 24, 1997

Filed:

Sep 7, 1995

Appl. No.:

8/525378

Inventors:

Karl Frank Hens - State College PA
Joseph A. Grohowski - State College PA

Assignee:

Thermat Precision Technology, Inc. - Corry PA

International Classification:

B22F 102

US Classification:

75228

Abstract:

Provided is a powder and binder system for manufacturing sintered parts from particulate material, and a method of injection molding parts for sintering. The particulate material includes ceramic, metallic and intermetallic powders. Preferably, selected powder particles are coated with one or more additives depending on their shape and surface chemistry to create a powder system. The additives may include antioxidants, coupling agents, surfactants, elasticizing agents, dispersants, plasticizer/compatibilizers and lubricants. The surface active additives are designed to improve the interface between the powder and the binder. The powder system may be mixed or compounded with a binder system in an inert atmosphere to form a powder and binder system, or feedstock, for powder molding. The binder system, may contain one or more components which are removed prior to the sintering the powder. The powder and binder system may also be molded about an expendable core which is extracted prior to sintering.

US Patent:

59500638, Sep 7, 1999

Filed:

Mar 10, 1997

Appl. No.:

8/814284

Inventors:

Karl Frank Hens - State College PA
Joseph A. Grohowski - State College PA

Assignee:

Thermat Precision Technology, Inc.

International Classification:

B22F 102
B22F 312

US Classification:

419 5

Abstract:

Provided is a powder and binder system for manufacturing sintered parts from particulate material, and a method of injection molding parts for sintering. The particulate material includes ceramic, metallic and intermetallic powders. Preferably, selected powder particles are coated with one or more additives depending on their shape and surface chemistry to create a powder system. The additives may include antioxidants, coupling agents, surfactants, elasticizing agents, dispersants, plasticizer/compatibilizers and lubricants. The surface active additives are designed to improve the interface between the powder and the binder. The powder system may be mixed or compounded with a binder system in an inert atmosphere to form a powder and binder system, or feedstock, for powder molding. The binder system, may contain one or more components which are removed prior to the sintering the powder. The powder and binder system may also be molded about an expendable core which is extracted prior to sintering.