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

Analisis Tekstur Padalasan Stainless Steel 201 dengan Teknik Difraksi

ANALISIS TEKSTUR PADALASAN STAINLESS STEEL 201 DENGAN TEKNIK DIFRAKSI NEUTRON. Baja tahan karat jenis austenitik merupakan baja tahan karat yang banyak dipakai dalam industri, salah satunya adalah industri rumah tangga. Dalam penelitian ini dilakukan karakterisasi Stainless Steel (SS) 201 yang banyak dijual di pasaran. Sebelum dilakukan karakterisasi, plat SS 201 dipotong dengan ukuran 150 mm × 120 mm× 10 mm, kemudian dibuat lubang berbentuk alur pada kedua permukaan, sehingga alur berbentuk X Double V Groove (DVG), selanjutnya alur DVG dilas dengan sistem pengelasan multi pass menggunakan metode pengelasan Metal Inert Gas (MIG). Bahan yang sudah dilas kemudian dikarakterisasi dengan teknik difraksi neutron untuk mendapatkan pola difraksi dan pole figure pada daerah pusat lasan FusionZone (FZ), daerah terpengaruh panas Heat Affected Zone (HAZ) dan daerah logam dasar Base Metal Zone (BMZ). Selanjutnya pole figure dianalisis dengan perangkat lunak Beartex untukmenentukan arah orientasi dan kekuatan tekstur pada ketiga daerah tersebut. Dari penelitian ini dapat disimpulkan bahwa pada daerah pusat lasan butir kristalit terorientasi {110} dengan tipe Brass dengan indeks tekstur sekitar 3,12 m.r.d (multiple random distribution) yang ditunjukkan pada pole figure 200. Untuk daerah HAZ, tekstur paling kuat terorientasi pada {110} atau tipe Goss dengan indeks tekstur 4,8 m.r.d. Pada daerah logamdasar, tekstur secara dominan terorientasi kearah {010} atau tipe Cube dengan indeks tekstur tidak terlalu kuat, sekitar 1,53 m.r.d. Pada daerah pusat lasan, bidang (110) sejajar dengan sumbu normal (ND), dengan arah kristalit sejajar dengan arah pengerolan (RD) [112]. Pada daerah HAZ bidang (110) tersebut mengarah ke arah sumbu pengerolan [001], dengan indeks tekstur 1,5 kali lebih kuat dibanding FZ. Hal ini menunjukkan bahwa bidang (110) yang semula terorientasi kearah [112] pada FZ berubah menjadi sekitar 35,26º ke arah [001] pada daerah HAZ. Untuk daerah logamdasar bidang (010)mengarah sejajar dengan arah normal (ND) dan teksturmengarah pada arah pengerolan (RD) [100]

ANALISIS TEKSTUR PADALASAN STAINLESS STEEL 201 DENGAN TEKNIK DIFRAKSI

ANALISIS TEKSTUR PADALASAN STAINLESS STEEL 201 DENGAN TEKNIK DIFRAKSI NEUTRON. Baja tahan karat jenis austenitik merupakan baja tahan karat yang banyak dipakai dalam industri, salah satunya adalah industri rumah tangga. Dalam penelitian ini dilakukan karakterisasi Stainless Steel (SS) 201 yang banyak dijual di pasaran. Sebelum dilakukan karakterisasi, plat SS 201 dipotong dengan ukuran 150 mm × 120 mm× 10 mm, kemudian dibuat lubang berbentuk alur pada kedua permukaan, sehingga alur berbentuk X Double V Groove (DVG), selanjutnya alur DVG dilas dengan sistem pengelasan multi pass menggunakan metode pengelasan Metal Inert Gas (MIG). Bahan yang sudah dilas kemudian dikarakterisasi dengan teknik difraksi neutron untuk mendapatkan pola difraksi dan pole figure pada daerah pusat lasan FusionZone (FZ), daerah terpengaruh panas Heat Affected Zone (HAZ) dan daerah logam dasar Base Metal Zone (BMZ). Selanjutnya pole figure dianalisis dengan perangkat lunak Beartex untukmenentukan arah orientasi dan kekuatan tekstur pada ketiga daerah tersebut. Dari penelitian ini dapat disimpulkan bahwa pada daerah pusat lasan butir kristalit terorientasi {110} dengan tipe Brass dengan indeks tekstur sekitar 3,12 m.r.d (multiple random distribution) yang ditunjukkan pada pole figure 200. Untuk daerah HAZ, tekstur paling kuat terorientasi pada {110} atau tipe Goss dengan indeks tekstur 4,8 m.r.d. Pada daerah logamdasar, tekstur secara dominan terorientasi kearah {010} atau tipe Cube dengan indeks tekstur tidak terlalu kuat, sekitar 1,53 m.r.d. Pada daerah pusat lasan, bidang (110) sejajar dengan sumbu normal (ND), dengan arah kristalit sejajar dengan arah pengerolan (RD) [112]. Pada daerah HAZ bidang (110) tersebut mengarah ke arah sumbu pengerolan [001], dengan indeks tekstur 1,5 kali lebih kuat dibanding FZ. Hal ini menunjukkan bahwa bidang (110) yang semula terorientasi kearah [112] pada FZ berubah menjadi sekitar 35,26º ke arah [001] pada daerah HAZ. Untuk daerah logamdasar bidang (010)mengarah sejajar dengan arah normal (ND) dan teksturmengarah pada arah pengerolan (RD) [100]

Effects of the Preheating Temperature on the Crystal Structure and Texture of Martensitic Stainless Steel

Theoretically, the preheating temperature refers to the start martensite temperature (Ms), and the martensite transformation can be considered as the conservation of the invariant habit-plane in the lattice structure. The habit-plane is the interface plane between austenite and martensite as measured on a macroscopic scale.  From the calculation, Ms = 252 °C. The martensite formation can be affected by temperature or stress treatment. In this experiment, temperature treatment was conducted. The sample was treated at 250 °C ± 10 °C. Before and after the pre-heat treatment, the sample was characterized using the neutron diffraction method. BATAN’s Texture Diffractometer (DN2) with a neutron wavelength of 1.2799Å was used to characterize the sample. Analysis of the crystal structure showed that there are three phases before the preheating. The lattice parameters (a) obtained were as follows: for the -phase, a = 2.8501 ± 0.0004 Å; for the α’phase, a= b =2.517 ± 0.003 Å, and c= 3.581 ± 0.002 Å; for the -phase, a= 3.5884 ± 0.0004 Å, Rwp = 17.94%, and = 1.33. After preheating, only the -phase appears with a = 3.5830 ± 0.0005 Å, Rwp = 26.03%, and = 1.17. The orientation distribution function is modeled by the sample symmetrization model based on triclinic to orthorhombic sample symmetry. It shows that, before being preheated, the -phase has {100} <001> with texture index (F2 ) between 0.701 m.r.d. to 3.650 m.r.d., the α-phase has a texture index between 0.923 m.r.d. to 1.768 m.r.d., and the ’-phase has a texture index between 0.910 m.r.d. to 1.949 m.r.d. After being preheated, the -phase also has {100} <001> with a texture index between 0.846 m.r.d. to 3.706 m.r.d. It can be concluded, that because of the high preheating temperature, a phase change from martensite to austenite occurred that allowed the sample to be welded easily. After preheating, the -phase has the same cubic type orientation {100} <001>, and the texture index is nearly the same as that before preheating, with not martensite present

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

Effect of Rotational Speed on Static and Fatigue Properties of Rotary Friction Welded Dissimilar AA7075/AA5083 Aluminium Alloy Joints

In this work, rotary friction welding processes of dissimilar AA7075/AA5083 aluminium alloy rods with the diameter of 15 mm were performed at varying rotational speeds, typically 370 to 2500 rpm. The aim of this research is to improve mechanical properties, in particular, strength and fatigue performance of the weld joints. Several experiments including macro and microstructural examinations, Vickers microhardness measurements, tensile tests, fatigue tests and residual stress measurements were carried out. Results showed that at higher rotational speeds, typically 540 rpm or above, the dissimilar AA7075/AA5083 rotary friction weld joints revealed a static fracture in the AA5083 base metal side, indicating that the joint efficiency is more than 100%. It seemed that the best weld joint was achieved at the rotational speed of 1200 rpm, in which the friction heat was sufficient to form metallurgical bonding without causing excessive flash and burn-off. In such a condition, the fatigue strength of the weld joint was slightly higher than AA5083 base metal, but it was lower than AA7075 base metal. It was confirmed that the crack origin is observed at the interface followed by fatigue crack growth towards AA5083 side, and the growth of crack seemed to be controlled by microstructure and residual stress

Effect of Rotational Speed on Static and Fatigue Properties of Rotary Friction Welded Dissimilar AA7075/AA5083 Aluminium Alloy Joints

In this work, rotary friction welding processes of dissimilar AA7075/AA5083 aluminium alloy rods with the diameter of 15 mm were performed at varying rotational speeds, typically 370 to 2500 rpm. The aim of this research is to improve mechanical properties, in particular, strength and fatigue performance of the weld joints. Several experiments including macro and microstructural examinations, Vickers microhardness measurements, tensile tests, fatigue tests and residual stress measurements were carried out. Results showed that at higher rotational speeds, typically 540 rpm or above, the dissimilar AA7075/AA5083 rotary friction weld joints revealed a static fracture in the AA5083 base metal side, indicating that the joint efficiency is more than 100%. It seemed that the best weld joint was achieved at the rotational speed of 1200 rpm, in which the friction heat was sufficient to form metallurgical bonding without causing excessive flash and burn-off. In such a condition, the fatigue strength of the weld joint was slightly higher than AA5083 base metal, but it was lower than AA7075 base metal. It was confirmed that the crack origin is observed at the interface followed by fatigue crack growth towards AA5083 side, and the growth of crack seemed to be controlled by microstructure and residual stress

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