PENGARUH GRAIN ALIGNMENT TERHADAP RAPAT ARUS KRITIS SUPERKONDUKTOR YBa2Cu3O7-x

PENGARUH GRAIN ALIGNMENT TERHADAP RAPAT ARUS KRITIS SUPERKONDUKTOR YBa2Cu3O7-x. Superkonduktor YBa2Cu3O7-x telah disintesis dengan metoda melt texture growth. Strukturmikro dan struktur kristal sampel berturut-turut dikarakterisasi dengan SEM dan difraktometer neutron. Sedangkan rapat arus kritis sampel diukur dengan magnetometer SQUIDs. Data SEM menunjukkan adanya keteraturan sebagian butir-butir kristal pada arah tertentu. Analisis data difraksi neutron pada bidang [00l] terjadi peningkatan integrated intensity dan pada bidang [h00] dan [0k0] terjadi penurunan integrated intensity.Hal ini menunjukkan bahwa keteraturan butir-butir kristal tersebut sejajar bidang a-b. Disimpulkan bahwa salah satu pendukung terjadinya peningkatan rapat arus kritis superkonduktor YBa2Cu3O7-x adalah adanya keteraturan sebagian butir-butir kristal yang sejajar bidang a-b

Texture Characterization of the Copper Produced by Ecap Process Using Neutron Diffraction Technique

TEXTURE CHARACTERIZATION OF THE COPPER PRODUCED BY ECAP PROCESS USING NEUTRON DIFFRACTION TECHNIQUE. Texture and hardness characterization have been carried out on market copper samples that have gone through the equal channel angular pressing (ECAP) process. Neutron diffraction technique had been used for obtaining an average crystalline texture in a particular volume non destructively to the sample. The ECAP process is carried out once (1 pass) with some parts that have been plastically deformed and some parts that have not been deformed. Crystalline texture and hardness were observed in the deformed and non-deformed parts. Initial characterization was carried out by X-ray diffraction (XRD) followed by measurement of crystal texture using the neutron diffraction technique, while hardness was tested using the Vickers method. Rod-shaped sample with a diameter of 10 mm. Texture observations were performed at the center of the sample with a neutron beam limiting slit of 5x5 mm2 . There was an increase in hardness in the deformed position compared to the undeformed one. The texture that occurs is in the form of fibers with different directions and indexes, sequentially as follows: position 1, [111] of 4.96 m.r.d., position 2, -[111] of 1.86 m.r.d. and position 3 [010] of 2.44 m.r.d. , position 4 orientation is distributed on [011], [013], [115], [235] fibers with a texture index range of 1.07–1.33 m.r.d