Determining interphase boundary orientations from near-coincidence sites
- Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Materials Science and Engineering Dept.
A transmission electron microscope (TEM) study was made of the interphase boundary structure of delta plates precipitated from the gamma phase in alloy 718. A variety of interfacial defects were examined and identified. These results, together with available data from bcc laths in fcc Ni-Cr alloys, were used to develop a method for predicting precipitate orientation relationships and boundary orientations. The method employs a geometric matching approach in three dimensions based upon the concept of near-coincidence sites. It is suggested that precipitates in a given system select an orientation relationship which produces the greatest areal density of near-coincidence sites and that the habit plane adopts an orientation that yields the greatest area of boundary containing contiguous near-coincidence sites.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 651060
- Journal Information:
- Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Vol. 29, Issue 8; Other Information: PBD: Aug 1998
- Country of Publication:
- United States
- Language:
- English
Similar Records
A TEM study of the crystallography and interphase boundary structure of [alpha] precipitates in a Zr-2. 5 wt% Nb alloy
Atomistic simulation of an f.c.c./b.c.c. interface in Ni-Cr alloys