Some characteristics of the austenite-martensite transformation as determined by a simplified electrical resistivity tec
- PDF / 871,412 Bytes
- 4 Pages / 569 x 813.28 pts Page_size
- 23 Downloads / 174 Views
Material
Stress
Total Initial Tritium Conc., At. Pet
Pure Ti Pure Ti Pure Ti Pure Ti Pure Ti Ti-8AI-IMo-IV
Unstressed 80 pct Y.S. 200 hr, 600~ 13.5 pet Y.S. 200 hr, 600~ 80 pet Y.S. 200 hr, 450~ 24 pct Y.S. 200 hr, 450~ 63 pet Y.S. 200 hr, 600~
0.76 0.76 0.76 0.76 0.76 0.48
ResidualTritium in a-Titanium, At. Pct 0.65 0.13 0.3 0.10 0.13 0.096
at the a-fl interface; however, additional experiments a r e n e e d e d to s u b s t a n t i a t e t h i s p o s t u l a t e . By employing longer emulsion times, it was possible t o o b t a i n t h e r e s i d u a l c o n c e n t r a t i o n of t r i t i u m r e m a i n ing in a-titanium solid solution for these experiments. T h e r e s u l t s a r e s h o w n i n T a b l e III. A t s t r e s s l e v e l s a b o v e 50 p c t of y i e l d s t r e n g t h a p p r o x i m a t e l y 15 p c t of i n i t i a l h y d r o g e n w a s r e t a i n e d i n a-titanium solid solution on quenching from elevated tempe rature.
Some Characteristics of the Austenite-Martensite Transformation as Determined by a Simplified Electrical Resistivity Technique K . A . T H O R N B U R G , D. P . D U N N E , A N D C . M . WAYMAN
IN t h e
c o u r s e of a r e c e n t i n v e s t i g a t i o n of t h e e f f e c t of t h e d e g r e e of a u s t e n i t e o r d e r i n g o n t h e M s t e m p e r a t u r e of t h e m a r t e n s i t e t r a n s f o r m a t i o n i n F e - P t a l l o y s , 1 a s determined by electrical resistivity vs temperature m e a s u r e m e n t s , it b e c a m e a p p a r e n t t h a t c e r t a i n f e a tures of the transformation may be overlooked when conventional experimental techniques are employed. For example, when electrical resistance measurem e n t s a r e m a d e o n a p o i n t - b y - p o i n t b a s i s e v e r y few degrees by employing a bridge and galvanometer, the e f f e c t s of m a r t e n s i t e b u r s t s a n d r e c a l e s c e n t h e a t i n g may be partly obscured. These effects may be further o b s c u r e d b y t h e c u s t o m a r y u s e of a h e a t e d o r c o o l e d l i q u i d b a t h to e f f e c t t e m p e r a t u r e c h a n g e s . The method employed in the present work involves t h e c o n t i n u o u s m e a s u r e m e n t of e l e c t r i c a l r e s i s t a n c e a s a f u n c t i o n of t e m p e r a t u r e b y m e a n s of a n x - y r e -
K. A. THORNBURG and C. M. WAYMAN are with the Department of Metallurgy and Mining Engineering, University of Illinois at Urbana-Champaign, Urbana, Ill. D. P. DUNNE, formerly with the University of Illinois at Urbana-Champaign, is presently at Wollongong University College, Wollongong, N.S.W., Australia. Manuscript submitted February 18, 1971. 2302-VOLUME 2, AUGUST 1971
This study has been conducted at Astropower Laboratory, McDormell Douglas Corp., under contract NAS-7-488, sponsored by the National Aeronautics and Space Administration, Washington, D.C., with Mr. R. Raring as Project Scientist.
I. N. A. Tinct, T. L. Mackay, S. K. Asunmaa, and R. G. IngersolhASM Trans. Quart., 19
Data Loading...
