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is a multipurpose, fully-automated horizontal Xray diffractometer that allows many types of applications. SmartLab's expandable system and the Cross Beam Optics (CBO) enable the realization of various optical configurations. The optics of the CBO system permits easy switching of incident X-rays by simply changing the selection slit. The Cross Beam Optics mechanism allows user selectable switching between two incident X-ray beam without resetting or realigning the optical system. Both system geometries are permanently mounted and permanently aligned to allow easy changeover for different applications. In the Rigaku SmartLab two Cross Beam Optics systems are available: CBO and CBO-E. The CBO lets the user select the Bragg-Brentano focusing method or parallel beam method using the parabolic multilayer mirror, while the CBO-E lets the user select Bragg-Brentano focusing method or convergent beam optics using an ellipsoidal multilayer mirror. The convergent beam optics enables high resolution measurements by the transmission method. This method is used to measure samples with low absorption coefficients and preferred orientation, such as pharmaceuticals. The Cross Beam Optics systems (CBO and CBO-E) can be combined with a Johansson type Ge crystal for monochromatization of the incident X-rays to the Kα1 (Kα1 system) [1]. One of the main applications of Kα1 X-rays is powder pattern indexing of unknown crystal structures. Since the diffracted X-rays are not obstructed in the Kα2, the separation of the overlapping Bragg reflections becomes easier in the Kα1 system. The Kα1 system is designed as the position of the focal point of the Johansson type crystal is corresponding to the conventional X-ray source. Due to the design of the Kα1 system it acts like a virtual X-ray source. Therefore, the CBO or CBO-E system can be used in the same way as the conventional Kα system. Consequently, the Kα system and the Kα1 system can be easily switched. The diffracted X-rays can be focused on the detector plane by means of using Kα1 monochromatized X-rays together with convergent-beam optics (CBO-E). If we consider this optical system, high-speed and high-intensity measurement can be realized, if the high-speed onedimensional position sensitive X-ray detector D/teX Ultra is used. In this presentation, we report outline of the optics on the Rigaku SmartLab system and discuss high-resolution measurement results by using CBO-E with and without CuKα1 system.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

In this work, an Al-bronze alloy is reinforced with TiC through reaction of the alloy melt with methane gas. The resultant alloy is then centrifugally cast in cylindrical molds. It is found that the surface at the inner diameter of the cast contained in-situ produced TiC as well as Fe-rich inclusions. Metallographic observations using optical and scanning electron microscopy confirmed the presence of TiC particles (30 % volume), alpha and beta grains including iron precipitates. Cylindrical pins are machined from the inner surface and tested under various conditions in a three pin on disk Falex machine. Pins are tested under a constant load of 2.86 MPa and friction and wear rates are determined from measurements of weight losses versus wear lengths. It is found that under the applied load the reinforced material exhibits high friction and relatively low wear when compared with the unreinforced material. Apparently, under these conditions the TiC particles become abrasive particles thus contributing to wear of the steel counter-face through three body abrasive wear.

No abstract