Titanium alpha

Other effects of the ionicity of the catalyst on its activity has been studied by Natta, PaSQUON, Zambelli and Gatti (66). The polymerization of propylene was carried out with alpha titanium trichloride and diethylberylium or triethylaluminum. They found that catalysts from the alkylberylium were more stereospecific than those from alkyl aluminum. On the other hand their study of titanium trichloride with diethylaluminum iodide, diethylaluminum bromide, diethylaluminum chloride or triethylaluminum showed that the greater stereospecificity was produced by the iodide containing catalyst. The less electrophilic catalyst produced greater crystallinity than the corresponding bromide or chloride component. 

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

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. 

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... 

Oxygen is soluble in alpha-titanium until the composition TiO 5 (alpha-case) is formed, with the oxygen atoms supposedly being randomly distributed in the octahedral interstices of the hexagonally close-packed titanium lattice. ... 

Con70] Conrad, H. and Jones, R, Effects of Interstitial Content and Grain Size on the Mechanical Behavior of Alpha Titanium Below 0.4 Tm, in [Jaf70], p. 489-501... 

DVIos70] Moskalenko, VA. and Pupsova,B.H., Influence of Alloying on the Plastic Deformation of Alpha-Titanium at Low Temperatures (in Russian), report from the Physico-Tfechnical Institute for Low Temperatures, Ukr. Acad. Sci., 1970... 

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

U-bend specimens were annealed with a yield strength of703 MPa (102 ksi) and a tensile strength of 772 MPa (112 ksi). Source A.J. Sedriks, P.W. Slattery, and E.N. Pugh, Stress Corrosion Cracking of Alpha Titanium in Nonaqueous Environments, Proceedings of ... 

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

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