Exploratory Study Of The Creep Characteristic For Titanium Deep-sea Pressure Shell

Pressure structure is the carrier and safeguard of the submarine and submersible. Titanium alloy has a high strength, corrosion resistance, low magnetic and many other advantages to replace traditional materials in the deep-sea pressure structure. However, compared with the traditional steel pressure structures, creep deformation of titanium alloy can’t be ignored. This paper study the creep property of titanium alloy and titanium pressure hull by titanium silk experimental, theoretical method, FE method and model experimental.Obtain this results:First, select creep constitutive equation and fit the creep parameters by titanium wire tensile testing at room temperature. It’s the base for creep calculation of deep-sea pressure hull.Second, analyze the creep property of spherical shell and ring-stiffened cylindrical shell by numerical method. Through series calculation, provide its property of creep displacement and stress redistribution for reference. Pilot study the creep influence on geometric imperfection amplitude and stability of spherical shell and ring-stiffened cylindrical shell with geometric imperfection or hole.Third, based on general equation, this paper solve the creep and stress redistribution transient solution of the ring-stiffened cylindrical shell. The results agree well with the finite element solution. It’s conductive to theoretically analyze creep property of ring-stiffened cylindrical shell.Finally, design a method for creep test of pressure hull structure, a compressive creep test of titanium alloy ring-stiffened cylindrical shell model were conducted, measured the TC4 compressive creep of titanium alloy pressure hull structure for the first time, and compared with the results of numerical calculations, validate the reliability of numerical calculation result.