Alpha titanium alloys

Crevice Corrosion resistance of Alpha Titanium Alloys depends on Impurity Content/Alloying Additions... 

Alpha-titanium alloys. These alloys range in yield tensile strength from 173 to 483 MPa. Variations are generally achieved by alloy selection and not heat treatment. They usually contain alpha stabilizers and have the lowest strengths. However, they are formable and weldable. Some contain beta stabilizers to improve strength. Alpha-titanium alloys are generally in the annealed or stress-relieved condition. They are considered fully annealed after... 

Ti-5Al-2.5Sn is a medium-strength, all-alpha titanium alloy. It has very high fi acture toughness... 

Heat-treated bar. Thermal expansion is typical of other near-alpha titanium alloys. Sovirce IMI Titaniiun High-Ttemperature Alloys brochure... 

W. J. Evans. Optimising mechanical properties in alpha + beta titanium alloys. Mater Sci Eng A 243 %%, 1998. 

It is shown here that alpha, beta and alpha-beta titanium alloys can be friction stir welded. The phase transformations that occur in the nugget region and the heat affected zone are discussed. Residual stresses were found to be quite high in the present work. Tensile properties in transverse direction were... 

Many different titanium alloys have been developed for a large variety of applications. Titanium alloys are generally classified according to the equilibrium phases present in their microstructure at room temperature (Ref 1). They can be classified as commercially pure (CP) alloys and alpha alloys that mainly contain the hep phase, alpha-beta alloys that contain both phases, and metastable beta alloys and beta alloys that consist largely of the bcc phase. 

These alloys have an hep crystal structure known as alpha phase. The beta-transus temperature of CP titanium alloys is -910 15 °C (1670 27 °F), depending on the oxygen content (Ref 1). These alloys are not strengthened by heat treatment, like some other titanium alloys. They also have excellent corrosion resistance in seawater and marine environments. 

Milling summarizes the machining processes of square shoulder-, face-, profile-, and slotmUling. Titanium means titanium alloys (alpha and beta) used as a high strength, light weight, and corrosion resistant material f.e. in aerospace, medical, and automotive applications. 

Industrial grades of pure titanium have relatively low tensile strength in comparison to alpha-beta stabilized alloys such as Ti6A14V. Therefore, the majority of industrial uses for titanium incorporate the alpha-beta alloys and as such these are the focus of most adhesion studies.As with other metals, there is a large range of pre-treatments available for titanium and its alloys, as indicated in Table 1. 

Metallurgical classification. The crystallographic structure of titanium exhibits a phase transformation from a low-temperature close-packed hexagonal arrangement (i.e., a-hcp, alpha-titanium) to a high-temperature form body-centered cubic crystal lattice (i.e., 6-bcc, beta-titanium) at 882°C. This transformation can be considerably modified by the addition of alloying elements (Table 4.52) to produce at room temperature alloys that have all alpha, all beta, or alpha-beta structures. 

Therefore, the basic properties of titanium and its alloys strongly depend on their basic metallurgical structure and the way in which this is manipulated in their mechanical and thermal treatment during manufacture. Four main types of titanium alloy have been developed, and hence titanium alloys fall into the four categories alpha, near alpha, alpha plus beta, and beta. 

Titanium alloys have the best corrosion resistance of the metals and alloys typically used in seawater. Titanium is a passive film-forming alloy and retains excellent resistance in both low and high velocity seawater. Some titanium alloys, specifically the all alpha and near-alpha alloys, do exhibit a susceptibility to stress corrosion cracking [72]. 

F 620, Specification for Alpha Plus Beta Titanium Alloy Forgings for Surgical Implants... 

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