Solidification control including pattern recognition

• US 5,841,669 A
• Filed: 01/26/1996
• Issued: 11/24/1998
• Est. Priority Date: 01/26/1996
• Status: Expired due to Fees

• Current Assignee: Howmet Research Corporation
• Original Assignee: Howmet Research Corporation
• Inventors: Purvis, Andrew L., Diehm, Randall S., Hanslits, Christopher R.
• Primary Examiner(s): Trammel, James P.
• Assistant Examiner(s): MILLER, CRAIG S
• Application Number:
  US08/592,723
• Time in Patent Office: 1,033 Days
• Field of Search: 364/496, 364/552, 364/554, 364/468.17, 364/468.04, 364/138, 364/148-151, 148/404, 164/1, 164/47, 164/122-122.1, 164/4.1-45.7, 164/154.1, 395/1, 395/10, 395/20-22, 395/902, 395/903, 395/906
• US Class Current: 702/179
• CPC Class Codes: B22D 27/045 Directionally solidified castings
• CPC Class Codes: B22D 46/00 Controlling, supervising, not restricted to casting covered by a single main group, e.g. for safety reasons controlling or regulating in general G05

Abstract

A method of predicting a grain condition in a directionally solidified casting, comprises generating thermal history data for a directional solidification casting process, determining a plurality of casting process variables that statistically influence a plurality of different grain conditions, identifying each grain condition by determining a function containing values of each selected variable, and categorizing the selected variables with respect to variance among and between the different grain conditions to determine a pattern between the selected variable and the grain conditions.

Claims

1. A method of altering a grain condition in a directionally solidified casting, comprising generating thermal history data for a directional solidification casting process, determining a plurality of casting process variables that statistically influence a plurality of different grain conditions, identifying each grain condition by determining a function containing values of each selected variable, and categorizing the selected variables with respect to variance among and between the selected variables and the grain conditions, and altering a selected variable of the casting process to alter a grain condition of a casting made thereby.

2. The method of claim 1 wherein the thermal history data is generated from respective models representative of one of the grain conditions.

3. The method of claim 1 wherein the grain condition is identified by generating a linear discriminant function for each grain condition.

4. The method of claim 3 wherein the selected variables are categorized using the linear discriminant functions generated for each grain condition.

5. The method of claim 1 wherein one or more selected process variables are altered in the single crystal process to alter a grain condition of the single crystal casting.