Similar to other metals, the shrinkage behavior of titanium pipes during casting also undergoes changes from liquid to condensed solid and then to solid. This shrinkage behavior is usually divided into volume shrinkage and linear shrinkage. Body shrinkage reflects the overall volume change during the titanium tube casting process. As the total body shrinkage is equal to the volume of concentrated shrinkage cavities in the casting plus the volume of shrinkage porosity, the solidification shrinkage behavior during the alloy casting process is related to the body shrinkage of the alloy, which determines the characteristics of shrinkage cavities and porosity defects in titanium alloys. This is of great significance for understanding the formation of shrinkage cavities and porosity defects in titanium tubes.

The important factors affecting the solidification shrinkage of titanium pipes include alloy elements, casting materials, and casting structure. Due to the influence of alloying elements on the crystallization temperature interval of titanium tubes, just like their influence on flowability, the solidification shrinkage of titanium tubes first depends on the characteristics of the added alloying elements, that is, the size of the crystallization temperature interval formed between titanium and alloying elements. Eutectic titanium tubes with narrow crystallization temperature intervals have good flowability and are prone to forming concentrated shrinkage pores, while titanium tubes with wide crystallization temperature intervals have poor flowability and are prone to forming dispersed shrinkage pores, i.e. shrinkage porosity.

Due to its excellent physical properties, titanium tubes, as an excellent structural material, can compete with stainless steel and nickel alloys for application scope. In many departments of the national economy, the use of titanium tubes has increased product life, equipment reliability and productivity, accelerated process, improved labor conditions, and all of these have achieved significant economic benefits.