Titanium Matrix/Continuous Fiber/Continuous Fiber Composite Interface Interactions and Their Influence on Mechanical Properties
Abstract
Research on the influence of the interface on the mechanical properties of Ti-6Al-4V metal matrix composites (MMC) containing Borsic, SiC and B4C/B continuous fibers is reported. The potential high temperature application of the Ti MMC was the basis for thermal fatigue experiments. The mechanical measurements included monotonic and cyclic mixed mode testing. In the testing it is found that the crack follows the matrix/fiber interface for angles from transverse loading up to about 45 deg and propagates normal to the fiber for higher angles and longitudinal loading. This leads to properties that are bimodal in behavior, poor in the first case and higher in the second case. An analysis of diffusion down the interface and into the matrix is described and data presented for both thermal fatigue and isothermal treatments. TEM, EELS and AES results show the interfaces in the Ti MMC to contain very complex chemical, crystallographic and morphological features that are modified by exposure to humidity or a sulfur bearing environment. In addition segregation to the interface and its effect on the cohesive energy was analyzed with a non- equilibrium thermodynamics model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 06, 1984
- Accession Number
- ADA147504
Entities
People
- Harris L. Marcus
Organizations
- University of Texas at Austin