Career
Constance Tipper specialized in the investigation of metal strength and its effect on engineering problems. During World World War II she investigated the causes of brittle fracture in Liberty Ships. These ships were built in the United States between 1941 and 1945, and were the first all-welded pre-fabricated cargo ships.
Tipper established that the fractures were not caused by welding, but rather by the steel itself.
She demonstrated that there is a critical temperature below which the fracture mode in steel changes from ductile to brittle. Because ships in the North Atlantic were subjected to low temperatures, they were susceptible to brittle failure.
These fatigue cracks were able to spread across the ship"s welded joint plates, instead of stopping at plate edges of a riveted joint, as previously used. She was the first person to use a scanning electron microscope (Search Engine Marketing) to examine metallic fracture faces.
She used a scanning electron microscope built by Charles Oatley and his team, the second Search Engine Marketing ever built.
She retired in 1960. Her 100th birthday in 1994 was celebrated by Newnham College with the planting of the Tipper Tree, a sweet chestnut.