| Thad Vreeland Jr. | |
| Birth Date: | 20 October 1924 |
| Birth Place: | San Marino, California, U.S. |
| Death Place: | Arcadia, California, U.S. |
| Nationality: | American |
| Fields: | Materials Science |
| Workplaces: | California Institute of Technology |
| Alma Mater: | California Institute of Technology |
| Doctoral Advisor: | David S. Wood |
| Known For: | Research in Dislocation Mechanics in metals |
Thad Vreeland Jr. (October 20, 1924 – August 9, 2010) was an American materials scientist. He was Professor of Materials Science at the California Institute of Technology.
Vreeland's career at Caltech began with his B.S., earned in 1949 and his Ph.D. in 1952. He served as Professor of Mechanical Engineering and then Professor of Materials Science from 1954 to 1991, and afterward Professor Emeritus.
Vreeland's work on the mechanics of plastic deformation in solids and especially on dislocation behavior during the 1950s and through 1960s and 1970s was widely cited. He collaborated with his colleagues at Caltech, including David Wood.[1] He was active in the study of shock wave consolidation in powdered metals and developing methods for the measurement of strain in multilayer semiconductors using x-rays in the 1980s.