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A study was made of 20 cases of fracture involving the tibial condyles in the last 10 years. Open reduction was used in 19 patients. Non-surgical treatment was employed in only one patient with severe comminuted fracture. There were five medial, one lateral collateral, one anterior, and two posterior cruciate ligaments injured, and all ligaments were repaired. Results were judged using Hohl score.

Twenty-one patients with fractures of the lower end of the radius were investigated.The results were as follows:1) The cases with good anatomical results showed good functional results, whereas the clinical results were not so poor as the X-ray findings.2) Percutaneus Kirschner wire fixation was considered to be desirable for the unstable fractures.3) The best position for maintaining normal alignment and minimizing deforming forces is supination.

A group of 10 patients with unstable knees due to a combination of a medial meniscal tear with a rupture of the anterior cruciate ligament was studied to assess the effects of treatment. The results were assessed both subjectively and objectively. It was concluded that in patients with this combined lesion, it would be preferable to perform anterior Cruciate reconstruction using a bone-tendon-bone graft at the same time as the meniscal suture or meniscectomy.

Some of the physical and thermodynamic properties of III–V liquids can be explained by assuming that the liquids have a dual structure. The thermodynamic model which has been established for the present paper is a partially associated solution model. It was constructed on the assumption of the existence of associated complexes. The asymmetry of the liquidus curve and the amount of excess free energy determined from the phase diagram analysis can be explained by using the model. Some of the thermodynamic parameters obtained in this study are found to have important physical meanings. The interaction parameter between monoatomic species, ωA,B is in a good agreement with the theoretical value proposed by Stringfellow. The heat of formation of associated complexes can be represented explicitly in terms of the spectroscopic ionicity and the dehybridization factor. The free energy of formation is empirically evaluated to be 20-6(fi −0.17)RT−35,000fiDcal/mol for III–V binary liquids.

Mechanisms of multiple necking and deformation of fibre composites have been studied, using single tungsten fibre composites prepared by a plating method. It is concluded that the multiple necking results from local transfer of load from fibre to surrounding matrix. Processes of plastic deformation of the compositesat various stagesare discussed, and the characteristics of each stage are described. Neck spacing with 2–6% elongation decreased with increase in elongtion but remained constant above 6% elongation. Multiple necking occurred when the volume fraction of fibre was smaller than a critical value. The critical value determined. for each composite indicated that a strong matrix yielded large critical value.

By employing a single thick molybdenum fibre-copper matrix composite with very weak interfacial bonding, it was confirmed that flow stress, internal stress, effective stress and change in flow stress due to change in strain rate of the composite obey the simple rule of mixtures; strain-hardening exponent, stress exponent of strain rate, effective stress exponent of dislocation velocity and activation volume obey the modified rule of mixtures in the whole range of plastic deformation of the composite. This means that the inherent features of the fibre in the present composite were conserved beyond the failure strain of the fibre tested alone, and the above deformation parameters of the composite were, to a first approximation, determined by the inherent parameters of the fibre and the matrix.

By using the same single crystal examined by Auvray et al. [ Acta metall. 29 , 1061 (1981)], three independent investigations on the structure of Guinier-Preston (G.P.) zones have been performed by means of field ion microscopy, high resolution transmission electron microscopy and small-angle X-ray scattering measurements. The results were essentially self-consistent in terms of shape, size and number density of G.P zones and agreed with the previous result of Auvray et al . The main result is that the majority of G.P. zones are single layer, but multilayer zones co-exist, with up to 10–20% of the zones being in this form. The structure of G.P. zones and the related interpretation of experimental results are discussed.

Isothermal sections from 700 to 1000°C of the Ti-rich corner of the Ti–Mo–Al ternary phase diagram were determined by analysing quantitatively the α and β phases within the two-phase field using the electron-probe X-ray microanalyser. High accuracy can be achieved with a small number of specimens and treatments, and the method is suggested as a standard procedure for ternary phase-diagram determination. The solubility of molybdenum in the α phase is 0·6–0·75 wt.- % at 700–800°C, and in α2 ∼ 1·2 wt.-%Mo. Tie lines in the α + β field were determined, their average inclination being ∼−0·07 wt.-%Al/wt.-%Mo. This is also the average slope of the α + β/α+α2 + β phase boundary, whose location was determined from the abrupt rotation of tie lines, without the limitatioll that arises in other methods. by the need to resolve the α2 phase. The boundary appears at a low aluminium content, in agreement with recent reports on the evidence of ordering in Ti-AI alloys with 6 wt.-%Al or less. A method for checking...

The structure of an Fe83B17 amorphous alloy was examined in detail, mainly by means of small-angle X-ray scattering (SAXS) measurements. The electron density-density correlation derived from the observed intensity had the following characteristic features: a strong correlation concentrated in the short radial distances within about 1.2 nm and a rather weak correlation towards larger distances. After quantitative analysis, it was concluded that a compositional fluctuation occurs on a fine scale of about 1 nm in the amorphous Fe-B alloys, even though phase separation is not present as completely as in the structure model proposed by Boudreaux. Electrical resistivity measurements as well as transmission electron microscope (TEM) observations were performed to investigate the crystallization process. By using the theoretical equation of electrical resistivity reported by Landauer, the temperature dependence for the partially aged amorphous alloys was analysed. The volume fraction of crystalline phase estimated from the present analysis was in good agreement with the results obtained from TEM observation.

Atlanto-Axial Rotatory fixation is rather an uncommon condition. We experienced 6 such cases in children recently. We terated 4 cases conservatively and one chronic case and one case associated with Os odontoideum surgically.All clinical results were satisfactory. We duscussed about the diagnosis and the treatment of atlanto-axial rotatory fixation in this report.

The change in structure of an amorphous Fe-P-C alloy during ageing was examined using small-angle X-ray scattering (SAXS) measurement and transmission electron microscopy. The SAXS intensity was related to two different types of scattering regions depending on ageing time and temperature. The major scattering was from the crystalline particles, which had two-phase lamella structures. The average thickness of the lamellae remained constant at about 5 nm during ageing. The interlamella distance was three to five times the lamellar thickness in the regular packing region. Another minor scattering was interpreted as being caused by the local ordering of atomic configuration in the amorphous state. The average size of the scattering region was 1.8 to 2.4 nm and quite similar to the critical range proposed by Giessen and Wagner, beyond which the shortrange order disappears.

By using the single carbon-steel fibre-copper matrix composites, the important parameters controlling dislocation motions in the fibre, matrix and composite, namely flow stress, internal stress, effective stress, change in flow stress due to change in strain-rate or temperature, stress exponent of strain-rate, effective stress exponent of dislocation velocity, activation volume and activation enthalpy were measured at the stage in which the mechanical interaction between the components was negligible. It was found that all the composite parameters were determined only by the properties of the components and for each parameter, a modified rule of mixtures was derived.

A theoretical model of the longitudinal strength of brittle fibre-reinforced composites with brittle reaction zones was presented for both cases of strongly and weakly bonded fibre/brittle zone interfaces. First, on the basis of the fracture mechanics, a model of the strength of the fibres coated with strongly adhering brittle zones was proposed as a function of the thickness of the brittle zones. Next, the conditions under which debonding occurs at the interfaces were investigated with the aid of the shear lag analysis proposed by Cox. The theoretical model was then examined using composites with strongly and weakly bonded interfaces. The proposed model agreed fairly well with the experimental results. Finally, the permissible thickness of the brittle zone below which no reduction in fibre strength appears was calculated, using the proposed theory, under the condition of strong interfacial bonding, for carbon, boron and silicon carbide fibres which are of practical use. The calculated values of the thickness were smaller than 1 μm.

Eight cases of congenital dislocation of the hip were treated in our hospital with functional cast. Two cases failed in reduction by the Palvic Harness, and 6 cases were not treated before one year old. They were treated with our cast for 8 weeks after manual reduction. This cast enables the patients to move legs cephalad and caudal a little in axillar position. All cases obtained good results.

The embedded molybdenum fibre in a copper matrix composite was elongated apparently uniformly although the interface was so weak that necking in the fibre could not be suppressed by the matrix. To explain this result, a possible mechanism was suggested where suppression of necking in the fibre is caused by strain hardening of the composite as a whole and by an increment in strain rate in the cross-section where the fibre starts necking, but the incremental deformation amount and the incremental strain rate of the cross-section are small. On the basis of this mechanism, and with the aid of Hart's criterion, a new instability approach to tensile behaviour of the composite is presented. It was found that the stability of the composite is determined mainly by the strain-hardening exponent of the composite, which is determined by the modified rule of mixtures. The present derived condition of instability of the composite is in good agreement with that proposed by Mileiko.

The curvature of the human femoral condyle can be represented by the Archimedean spiral. The center of the Archimedean spiral was found to be situated in the attachment of P. C. L., M. C. L. and L. C. L. of the femoral condyle.

In order to examine the scattering of conduction electrons from Guinier-Preston (GP) zones, the electrical resistivity (ρ) and the Hall coefficient have been measured. Quantitative information on the microstructure of aged alloys was obtained from small-angle X-ray scattering measurements. The resistivity behaves anomalously during isothermal ageing; it increases to a maximum, then decreases and reaches a value corresponding to the steady state of the growth of GP zones. A further decrease occurs when the θ˝ phase begins to precipitate. During these changes, the zone size increases, and reaches a constant value which is slightly larger at higher ageing temperatures. The change in volume fraction (V f) of precipitated zones is quite similar to the change in zone size. It was found that the function (ρ - ρAsQ)/V f depends on the zone size. The origin of the resistivity maximum is discussed, based on the theory proposed by Hillel, Edwards and Wilkes.

The pseudoquaternary phase diagram of the Ga-In-As-Sb quaternary system has been determined experimentally. The liquidus data were obtained by DTA, and the solidus data were determined by the liquid phase epitaxial method. This phase diagram and the study of composition variations in the epitaxial layers indicate that the Ga-In-As-Sb quaternary system can form the lattice-matched GaxIn1-xAs1-ySby solid solutions on the GaSb and/or InAs binary compounds in the composition range of 0 ⩾ x < 0.3 and 0.6 < x ⩾ 1.0.

The commercial silver-Ni, or W, or CdO contacts have been produced mainly by the powder metallurgy, which seems to be rather expensive from a metallurgical viewpoint. In order to develope a more economical method, the infiltration method used to prepare fiber-reinforced metal composites was applied in the present work to make silver composite contacts with Ni continuous thin wire, alumina whisker SAFFIL, and carbon chopped fiber.Ag-Ni composite was successfully prepared by an unidirectional solidification, and Ag-alumina whisker and Ag-carbon fiber by a centrifugal infiltration method. The Ag-30wt%Ni (No.2) composite contact was found to have a superior contact property than the traditional Ag-15wt%Ni contact, and to be able to save a considerable amount of silver. The Ag-30vol% carbon composite contact showed a comparable property to Ag contacts, though its contact resistance was slightly larger.