Showing papers on "Titanium published in 1970"
TL;DR: In this article, the martensitic transformations involved were studied by X-ray diffraction and the composition dependence of the Martensitic-transformation characteristics, such as Ms, Mf, As and Af-temperatures, were determined.
Abstract: Alloys of compositions near AuTi, PdTi, and PtTi are B19-type orthorhombic at room temperature and, at higher temperatures, have an ordered CsCl-type structure (B2-type). The martensitic transformations involved were studied by X-ray diffraction. The composition dependence of the martensitic-transformation characteristics, such as Ms, Mf, As and Af-temperatures, were determined. Lattice constants of the high-temperature phases are given.
262 citations
Patent•
02 Jul 1970TL;DR: An alloy capable of having the property of heat recoverability imparted to its components is defined in this article, comprising 49.1 to 50.2 atomic percent of titanium, 2.5 to 4.7 atomic percent iron and the remainder nickel.
Abstract: An alloy capable of having the property of heat recoverability imparted thereto comprising 49.1 to 50.2 atomic percent of titanium, 2.1 to 4.7 atomic percent of iron and the remainder nickel.
232 citations
TL;DR: An experiment was performed wherein titanium porous coatings were applied to a wrought titanium bone implant, indicating approximately a twenty-fold increase over similar tests performed on uncoated control specimens.
Abstract: Recent results indicate varying degrees of bone ingrowth into porous metal and ceramic bodies. Such homogeneously porous ceramic and metal implants generally possess inadequate mechanical properties, limiting their application to low stress or nonstructural applications. An experiment was performed wherein titanium porous coatings were applied to a wrought titanium bone implant. These surfaces were achieved by plasma spraying of titanium hydride powder, depositing a mixture of wellbonded titanium-titanium oxide with pore diameters varying from .002 to .005 in.
Implant specimens were placed in sheep femora for periods of 14 and 26 weeks. No adverse affects were noted. Interface shear strengths were determined by torque tests which indicated approximately a twenty-fold increase over similar tests performed on uncoated control specimens.
138 citations
TL;DR: In this article, high-purity strontium, zirconium, and titanium alkoxides were synthesized and characterized as precursors for complex oxides.
Abstract: High-purity strontium, zirconium, and titanium alkoxides were synthesized and characterized as precursors for complex oxides. Simultaneous hydrolytic decomposition either of strontium and zirconium alkoxides or of strontium and titanium alkoxides was used to obtain nearly stoichiometric, ideally mixed SrZrO3 or SrTiO3 powders of high surface activity. As-prepared helium-dried SrTiO3 is crystalline before calcination. An ultraviolet radiation technique demonstrates the nucleation and growth of SrZrO3 crystallites in the calcination temperature range to 350°C. The experimental results are supported by ir, TGA, and X-ray diffraction data. The high degree of control over purity, mixing uniformity, and crystallite size demonstrates the value of the alkoxide precursor approach for the solution of reproducibility problems encountered in the synthesis of electrical-quality ceramics.
80 citations
78 citations
TL;DR: In this paper, a study of the diffusion of titanium ion in titanium dioxide has been made by diffusing the radioisotope titanium-44 into single crystal rutile at selected temperatures in the range of 900° to 1300°C.
72 citations
TL;DR: Titanium in TiO2 minerals was differentiated from that isomorphously substituted into minerals by the use of dihydrogen hexafluorotitanate (hydrofluotitanic acid, H2TiF6) as discussed by the authors.
Abstract: Titanium in TiO2 minerals was differentiated from that isomorphously substituted into minerals by the use of dihydrogen hexafluorotitanate (hydrofluotitanic acid, H2TiF6), which selectively dissolved minerals containing substituted Ti4+, leaving free crystalline TiO2 minerals in the residue. Titanium analyses on the original samples and the residues remaining after H2TiF6 treatment, by both wet chemical (Tiron) and neutron activation methods, indicated that an average of 86 per cent of the titanium in seven kaolinite samples was present in the residual TiO2 form (largely anatase), whereas only 28 per cent in two bentonites was present in the TiO2 form. Residual Ti accounted for 100 per cent of the Ti in synthetic anatase and for 92 per cent of the Ti in coarse clay sized rutile, the latter value suggesting that about 8 per cent amorphous TiO2 was removed from the mechanically dry ground rutile by the H2TiF6 reagent. The Ti present as residual TiO2 in a variety of other samples ranged from 0 to 100 per cent.
69 citations
Patent•
31 Dec 1970
TL;DR: A sintered alloy comprising a carbide of preferably titanium and a steel matrix of an alloy steel containing chromium, molybdenum, copper and vanadium as alloying elements provides high temperature hardness and wear resistance as discussed by the authors.
Abstract: A sintered alloy comprising a carbide of preferably titanium and a steel matrix of an alloy steel containing chromium, molybdenum, copper and vanadium as alloying elements provide high temperature hardness and wear resistance. Preferred alloys contain 0.8 to 1.9% by weight of manganese and up to 80% by weight of carbide.
66 citations
TL;DR: In this article, anodic oxide films were prepared from pure aluminium, titanium, niobium, tantatlum and tungsten, and examined by direct transmission electron microscopy.
TL;DR: The influence of deviations from stoichiometry and titanium additions on the flow stress of polycrystalline Ni3Al has been determined in the temperature range of 196 to 1000 °C as mentioned in this paper.
Abstract: The influence of deviations from stoichiometry and titanium additions on the flow stress of polycrystalline Ni3Al has been determined in the temperature range — 196 to 1000 °C. The flow stress is found to be sensitive to small composition changes within the phase field. In particular, aluminium-rich deviations from stoichiometry produce significant strengthening in the compound. Titanium additions also result in strengthening but at the same time shift the peak in the flow stress—temperature curve to lower temperatures.
TL;DR: In this paper, augmented plane-wave (APW) calculations of the electronic structure of titanium have been carried out and the resulting Fermi surface is compared to that predicted by the model of Altmann and Bradley based on cellular calculations and the APW model of Loucks for zirconium.
Abstract: Augmented-plane-wave (APW) calculations of the electronic structure of titanium have been carried out. The resulting Fermi surface is compared to that predicted by the model of Altmann and Bradley based on cellular calculations and the APW model of Loucks for zirconium.
TL;DR: In this paper, a new phase, TiO 1.82, appears between Ti 5 O 9 and Ti 6 O 11, and is interpreted as a regular 1:1 intergrowth structure, Ti 11 O 20.
Abstract: Equilibrium oxygen pressures over titanium oxides in the composition range Ti 4 O 7 to Ti 6 O 11 have been measured between 1323° and 1423°K by equilibration with H 2 -H 2 O gas mixtures. The intermediate “shear structure” oxides show no detectable range of stoichiometry. A new phase, TiO 1.82 , appears between Ti 5 O 9 and Ti 6 O 11 , and is interpreted as a regular 1:1 intergrowth structure, Ti 11 O 20 . Thermodynamic data for the TiO n oxides (1.5 n
TL;DR: An X-ray diffraction study has shown the cyclooctatetraene ligand in cyclopentadienylcyclooctetraenetitanium to be π-bonded to the metal as mentioned in this paper.
TL;DR: In this article, the crystal structures of rhombohedral Ti 3 S 4 and hexagonal Ti 4 S 5 were determined by X-ray powder diffraction methods based on close packings of sulfur atoms of the types (chchchh ) 3 and (chhh ) 2, respectively.
Patent•
26 Jan 1970TL;DR: Interlayers of malleable tantalum-, columbium-, aluminum-, or titanium base metals are employed between layers of high-yield-strength aluminum-, titanium-, or zirconium-base metals as mentioned in this paper.
Abstract: Interlayers of malleable tantalum-, columbium-, aluminum-, or titanium-base metals are employed between layers of high-yield-strength aluminum-, titanium-, or zirconium-base metals and dissimilar layers of high-yield-strength-iron-, nickel-, or aluminum-base metals to provide metallurgically bonded metal composites having good shear strength and superior resistance to impact loading. The composites are useful, e.g., as transition joints, and are used to best advantage where gas-tight tubular transition joints are required. Transition joints composed of high-yield-strength titanium- or aluminum-base metals bonded to high-yield-strength stainless steel via an interlayer of tantalum- or columbium-base metal exhibit outstanding low-temperature properties, and composites of high-yield-strength zirconium-base metals bonded to such stainless steels via the same interlayers make superior transition joints for nuclear applications.
DOI•
01 Jan 1970TL;DR: In this article, the microstructure of a ternary alloy, Al-5 wt pct Ti, 1 wt Pct B, has been examined by optical and electron transmission microscopy, by selected area diffraction, and electron probe microscopy.
Abstract: The microstructure of a ternary alloy, Al-5 wt pct Ti, 1 wt pct B, has been examined by optical and electron transmission microscopy, by selected area diffraction, and electron probe microscopy, by selected area diffraction, and electron probe microanalysis. Particles of Al3Ti are found at the center of grains and there exist preferred epitaxial orientations between this compound and the surrounding aluminum. Particles containing titanium and boron occur at aluminum grain boundaries and have no preferred configurations with respect to the aluminum or to one another. It is concluded that the active heterogeneous nuclei are therefore Al3Ti and that particles of TiB2, AlB2, or a ternary compound are not active in this alloy. Grain size measurements in binary Al-Ti alloys suggest that particles of a nucleating phase must be present at concentrations as low as 0.01 wt pct Ti, and it is suggested that these could be Al3Ti if the existing binary phase diagram Al-Ti is in error.
01 Jan 1970
TL;DR: The paramagnetic center formed in anatase seems to be Ti(III)O6 having the holohedrized symmetry D4h as discussed by the authors, however, the numerical values of the small deviations of g from 2 are smaller than expected from the moderate anti-bonding characters of (xz, yz) relative to the xy-orbital.
TL;DR: In this article, phase formation and mass transport during the reaction of iodine-refined titanium with nitrogen at 760 Torr and 800 to 1200°C were described, where each titanium-nitrogen phase is present within the composition and temperature range of its thermodynamic stability.
Abstract: This paper describes phase formation and mass transport during the reaction of iodine-refined titanium with nitrogen at 760 Torr and 800 to 1200°C. Each titanium-nitrogen phase is present within the composition and temperature range of its thermodynamic stability. Between 882 and 1110°C there are the nitrides, TiN and Ti2N, and solutions of nitrogen in α and β-titanium. There is no β-titanium below 882°C or Ti2N above 1110°C. The growth of each phase layer involves some favorably oriented grains from among the many that are nucleated. Nitrogen concentration gradients exist in all phases. Nitrogen is the predominant diffusing species in all phases but a small amount of outward diffusion of titanium occurs through the nitrides, producing α-phase porosity above 1100°C. There is some porosity in the outer regions of TiN. All phases remain mechanically sound and coherent with each other. Changes in the relative proportions of phases during cooling are identified, which enables corrections to be made to kinetic data for the reaction.
TL;DR: In this paper, a cyclic compound consisting of the Ti-O-Si bond was obtained; its presence was confirmed by a study of the IR and NMR spectra, by elemental analysis, and by molecular-weight determination.
Abstract: Alkoxysiloxy derivatives of titanium and polymeric substances with Ti–O–Si bonds were prepared. The reaction of titanium tetra-isopropoxide or bis (acetylacetonato)di-isopropoxytitanium with tri-t-butoxysilanol led to the formation of the derivatives of [(ButO)3SiO]nTi(OPri)4−n (n=2 and 3) and those of [(ButO)3SiO]2Ti(AcAc)2 respectively. In both of these series, the absorption peak of the Ti–O–Si bond in the IR spectrum shifted toward a lower wave number from the compounds of n=2 to those of n=3. The reaction of titanium tetra-isopropoxide with di-t-butoxysilanediol, as expected, gave a polymeric substance. In the reaction with bis(tri-t-butoxysiloxy)-silanediol, however, an unexpected cyclic compound consisting of the Ti–O–Si bond was obtained; its presence was confirmed by a study of the IR and NMR spectra, by elemental analysis, and by molecular-weight determination. In order to obtain a linear polymer, the reaction of the titanium acetylacetonato chelate with the silanediols was carried out to give a...
Patent•
02 Mar 1970
TL;DR: A method for adding allOYing ELEMENTS SUCH AS ALUMINIUM, TITANIUM, and MOLTEN METALS was described in this paper, with the main purpose of creating a refined and enriched metalloy.
Abstract: A METHOD FOR ADDING ALLOYING ELEMENTS SUCH AS ALUMINIUM, TITANIUM TO MOLTEN METALS, SAID ELEMENTS BEING CAPABLE OF REACTING WITH THE ATMOSPHERE SURROUNDING THE METALS, COMPRISING INSERTING A WIRE ROD MADE OF THE ELEMENT INTO A MOLTEN METAL BATH AT A CONTROLLED SPEED, SAID ROD HAVING A CONTROLLED IZE, SO AS TO PRODUCE A REFINED AND PURIFIED METAL ALLOY.
01 Jan 1970
TL;DR: In this article, 15 deformation twinning modes which could occur in titanium and which involve shear strains less than unity and particularly simple shuffle mechanisms are presented, but only two of these modes have in fact been observed in titanium.
Abstract: Fifteen deformation twinning modes which could occur in titanium and which involve shear strains less than unity and particularly simple shuffle mechanisms are presented. However, only two of these modes have in fact been observed in titanium. These have {10 2} and 1} composition planes which involve the smallest shear and simplest shuffles respectively. Two further operative twinning planes, 2} and 4}, can be readily explained by a low shear mode and its conjugate which through a crystallographic degeneracy also have simple shuffles. No satisfactory mode to explain the reported 3} twin in titanium has been found. Structural restrictions on the twinning dislocations associated with the operative modes in titanium are also examined.