The first neutron texture diffractometer in China has been built at China Advanced Research Reactor due to the strong demands of texture measurement with neutrons from domestic user community. This neutron texture diffractometer has high neutron intensity, moderate resolution and is mainly applied to study the texture in the commonly used industrial materials and engineering components. In this paper, the design and characteristics of this instrument are described. The results for calibration with neutrons and quantitative texture analysis of Zr alloy plate are presented. The comparison of texture measurement among different neutron texture diffractometer of HIPPO at LANSCE, Kowari at ANSTO and neutron texture diffractometer at CARR illustrates the reliable performance of this texture diffractometer.

ANALISIS TEKSTUR ZIRCALOY-4 MENGGUNAKAN METODE WILLIAM–IMHOF–MATTHIES-VINEL (WIMV). Zircaloy-4 sebagai kelongsong bahan bakar nuklir telah banyak diteliti secara makroskopik maupun secara mikroskopik, namun penelitian menggunakan teknik difraksi neutron, terutama karakterisasi orientasi kristalit (tekstur) di Indonesia masih jarang dilakukan. Tujuan penelitian ini adalah untuk menerapkan metode WIMV pada karakterisasi tekstur bahan tersebut. Metode WIMV adalah salah satu metode analisis tekstur bahan yang diperoleh dengan teknik difraksi neutron atau difraksi sinar-X. Dari hasil analisis tersebut diperoleh pole figure 002 dengan indeks tekstur (F2) terbesar dibandingkan dengan pole figure yang lain yaitu 100, 101, 102 dan 110. Indeks tekstur (F2) pole figure 002 untuk incomplete pole figure, F2= 4,69 m.r.d dengan faktor reliabilitas RP0 = 3,28%, dan recalculated pole figure, F2 = 4,42 m.r.d. dengan RP1 = 2,97%. Semua pole figure diperoleh faktor reliabilitas dengan pole figure rata-rata RP0 = 6,60%, RP1 = 5,02%, entropy = - 0,5871, dan indeks tekstur, F2= 2,34 m.r.d. Hasil analisis bahan Zircaloy-4 tersebut menyimpulkan bahwa metode WIMV dapat digunakan untuk menentukan arah orientasi tekstur, dimana tekstur yang paling kuat mengarah ke <001> (arah sumbu c) dalam struktur hexagonal.TEXTURE ANALYSIS OF ZIRCALOY-4 USING WILLIAM-IMHOF-Matthies-VINEL (WIMV) METHOD. Zircaloy-4 as a nuclear fuel cladding has been widely examined macroscopically and microscopically, but research using neutron diffraction technique, especially the characterization of crystallite orientation (texture) in Indonesia is still rare. The purpose of this study is to apply the methods of William-Imhof-Matties-Vinel (WIMV) on the characterization of zircaloy-4 material texture. WIMV is one of data analysis method for textures materials obtained by neutron or x-ray diffractions technique. The analysis is obtained that 002 pole figure has the largest texture index (F2) compared to the others pole figures, that are 100, 101, 102 and 110. Index texture (F2) of pole figure 002 for incomplete pole figures, F2 = 4.69 m.r.d with a reliability factor RP0 = 3.28%, and recalculated pole figures, F2 = 4.42 m.r.d with RP1 = 2.97%. For all pole figures, it is obtained that a reliability factor of the average RP0= 6.60%, RP1 = 5.02%, entropy = - 0.5871, and texture index (F2) = 2.34 m.r.d. Data analysis showed that the WIMV method can be used to determine the direction of the crystallite orientation of the pole figure where the most powerful texture leads to the <001>(c-axis direction) in a hexagonal structure.

The monochromator for the new residual stress diffractometer at China Advanced Research Reactor (CARR) was simulated and optimized using SIMRES software. Objected the Fe (211) diffraction peak, the effect of horizontal and vertical curvature of Si (400) monochromator on Figure of Merit was studied to optimize the focusing parameters. With the optimal focusing condition, the influence of wafer thickness, number of wafers, packet height and gap of packets on performance of instrument was calculated consequently and the corresponding geometrical size was fixed. Finally, the design of the monochromator for the new residual stress diffractometer at CARR was completed.