PROBLEM TO BE SOLVED: To provide techniques for forming cast parts for medical devices suitable for contact with internal regions of patients.SOLUTION: Such parts can be small in scales {e.g., having a major axis less than 7.62 mm (0.3 inches), and/or a minor axis less than about 2.03 mm (0.08 inches)}, and can be formed from metals that have a high melting point and high reactivity with environmental components or mold surfaces, such as stainless steel and titanium alloys. Such techniques can include injecting molten metal into the sprue of a mold tree such that the side runners are backfilled after the molten metal impacts a closed end of the sprue. Side runners can be oriented in particular directions and positions to promote backfilling. As well, flask temperatures and the use of surfactants can also promote cast part formation, hindering the formation of surface defects.

Title
Cast parts with improved surface properties and methods for their production
Application Number
2007-251949
Publication Number
2008-080403
Application Date
September 27, 2007
Publication Date
April 10, 2008
Inventor
Onukuri Samardh
Deforce Brian S
Heaney Donald F
Potter Tracy J
Crawford William A
Assignee
Ethicon Endo Surgery
IPC
A61L 27/00
B22C 09/04