Material Komponen dan Konstruksi最新文献

{"title":"ANALISIS KERUSAKAN POROS GENERATOR PEMBANGKIT LISTRIK = DAMAGE ANALYSIS OF A POWER GENERATOR SHAFT","authors":"SA Soedardjo, Y BambangPurnomo","doi":"10.29122/MKK.V14I2.1661","DOIUrl":"https://doi.org/10.29122/MKK.V14I2.1661","url":null,"abstract":"The damage shafts of a power generator have analyzed. The background of this analysis is the shaft generators for electricity in Indonesia frequently are broken. The purpose of the analysis is to determine the cause of damage to the shaft generators. Methodologies used include interviews with the owners and employees at the site, visual inspection on site, visual inspection at the workshop, the workshop hardness testing, chemical composition in the laboratory and analysis based on several references. Analysis of the results obtained are: generator shaft number 1A fracture due to rotation overload, shaft number 1B is cracked circular in the fillet, shaft number 2 cracks oriented at an angle of about 45° to the axis of the shaft. The conclusion that can be taken, power generator shaft fractures due to the design of the fillets as a stress concentration is not perfect, excessive loads, and occurred material ductile fracture.Keywords : Shaft, power generator, hardness testing, chemical composationAbstrak Telah dianalisis kerusakan beberapa poros dari suatu generatorpembangkit listrik. Latar belakang analisis ini adalah seringnya terjadi poros generator pembangkit listrik di Indonesia yang patah. Tujuan dari analisis adalah untuk mengetahui penyebab kerusakan poros  generator pembangkit listrik. Metodologi yang digunakan antara lain  wawancara dengan pemilik dan karyawan di lokasi, pemeriksaan visual di situs, pemeriksaan visual di bengkel, uji kekerasan di bengkel, komposisi kimia di laboratorium dan analisis berdasarkan beberapa referensi. Hasil Analisis yang diperoleh adalah: poros generator nomor 1A patah karena terjadi kelebihan beban putaran, poros nomor 1B retak melingkar di daerah fillet, poros nomor 2 retak yang berorientasi pada sudut sekitar 45° terhadap sumbu poros. Kesimpulan yang dapat diambil, poros generator pembangkit listrik patah karena desain fillet sebagai sumber tegangan yang tidak sempurna, beban berlebihan, dan material mengalami patah ulet.Kata Kunci : poros, pembangkit listrik,uji kekerasan,komposisi kimia","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116303101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SERANGAN KOROSI SUMURAN (PITTING CORROSION) PADA PIPA ROLL BEARING DISTRIBUSI","authors":"H. Sunandrio, Laili Novita Sari","doi":"10.29122/mkk.v11i2.556","DOIUrl":"https://doi.org/10.29122/mkk.v11i2.556","url":null,"abstract":"Dalam instalasi explorasi minyak, peralatan yang digunakan untuk menyalurkan minyak mentah dari sumur minyak ke tangki - tangki penampungan melalui pipa distribusi. Dimana untuk membagi ke masing-masing tanki penampungan pada pipa distribusi unit penyaluran minyak yang dibuat dapatberputar dengan menggunakan roll bearing.Pada penelitian ini telah diamati kerusakan yang terjadi pada disuatu instalasi explorasi minyak yang mengakibatkan kebocoran. Hasil penelitian menunjukkan bahwa penyebab utama kerusakan pada roll bearing karena adanyaserangan korosi sumuran . Pada bagian dalam bearing pada kondisi beroperasi selalu bersentuhan langsung dengan cairan / minyak secara terus menerus yang mengandung air danelemen-elemen yang bersifat korosif. Dalam keadaan demikian maka clearence pada bearing akan membesar dan pada akhirnya akan timbul kebocoran. Pemeriksaan dan pengujian yang dilakukan terhadap roll bearing, meliputi :pemeriksaan fraktografi dan metalografi, uji kekerasan, analisa komposisi kimia, serta pemeriksaan dengan SEM dan EDAX. Data dari hasil pemeriksaan dan pengujian tersebut kemudian di analisa untuk mengetahui penyebab terjadinya kebocoran pada roll bearing tersebut.","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114597554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"METODE ANALISIS PATAH LELAH BAJA AKIBAT BEBAN LENTUR DINAMIS CANTILEVER","authors":"Harkali Setiyono","doi":"10.29122/MKK.V11I2.552","DOIUrl":"https://doi.org/10.29122/MKK.V11I2.552","url":null,"abstract":"Masalah yang penting untuk dipertimbangkan dalam desain struktur baja akibat beban dinamis adalah ancaman terhadap patah lelah.Oleh karena itu perlu dipahami mengenai mekanisme patah lelah yang akan dialami oleh struktur bajabeserta metode yang efektif untuk mengantisipasi jenis katastrofik ini. Didalam makalah ini diuraikan secara rinci mengenai pemanfaatan konsep Linear Elastic Fracture Mechanics (LEFM) untuk menganalisis perllaku patah lelah dari modeldesain baja cantilever akibat beban lentur dinamis. Didalam pendekatan LEFM, mekanisme patah lelah cantilever dianalisis berdasarkan besaran faktor intensitas tegangan disekitar ujung retak lelah dan teori empiris dari Paris Untuk memverifikasi pendekatan LEFM, maka desain baja cantilever juga diujimenggunakan beban lentur dinamis sampai patah lelah. Data hasil pengujian digunakan sebagai masukkan dalam analisis LEFM untuk mengestimasi perilaku perambatan dan kecepatan perambatan retak lelah dari desain baja cantilever akibat beban lentur dinamis.","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121898376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"KEKUATAN SAMBUNGAN LAS THERMIT REL R 54 UNTUK JALUR LINTAS ANGKUTAN BATUBARA","authors":"D. Purwanto","doi":"10.29122/mkk.v11i2.551","DOIUrl":"https://doi.org/10.29122/mkk.v11i2.551","url":null,"abstract":"Teknologi rel panjang saat ini biasa digunakan pada struktur jalan rel, dimana cara pembuatannya dilakukan dengan menyambung rel-rel standar dengan pengelasan setempat. Las thermit adalah salah satu metode pengelasan yang umum digunakan untuk menyambung rel. Pengelasan pada sambungan rel merupakan titik lemah terutama pada daerah pengaruh panas (HAZ), sebab jika terjadi beban kejut dapat mengakibatkan patah. Persoalan lain adalah mengatasibahaya tekuk, akibat gaya longitudinal karena perubahan suhu. Makalah ini membahas kajian kekuatan sambungan las thermit rel R 54. Metode evaluasi meliputi pemeriksaan cacat pengelasan, uji kekerasan dan uji kekuatan lentur.Dari hasil uji kekuatan lentur dapat disimpulkan bahwa tegangan rata-rata sambungan rel sebesar 8944,57 kg/cm2, sedangkan tegangan lentur akibat beban gandar 1193 kg/cm2 dan tegangan longitudinal akibat perubahan temperatur sebesar 441 kg/cm2 sampai 1102 kg/cm2. Dengan demikian sambungan las thermit rel R 54 dapat dioperasikan pada lintas angkutan batubara, sepanjang tidak diketemukan adanya indikasi cacat pengelasan.","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133058575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DAMAGE ANALYSIS AND DESIGN OF ADDITIONAL CROSS BEAM REINFORCEMENT USING FE METHOD = ANALISA KERUSAKAN DAN MERANCANG TAMBAHAN KONSTRUKSI PENGUAT UNTUK PENINGKATAN KEKUATAN BATANG LINTANG DENGAN TRIAL AND ERROR MENGGUNAKAN METODA ELEMEN HINGGA","authors":"Agus Sasmito, Tresna P. Soemardi, Harkali Setyono, A. Farid","doi":"10.29122/MKK.V13I1.1654","DOIUrl":"https://doi.org/10.29122/MKK.V13I1.1654","url":null,"abstract":"The paper focuses on structural damage of cross beam arms  for brake rod in the car of  train. Analysis of cross beam was based on the design and actual conditions of the car application. Investigation the cross beam damage was done by finite element analysis. Based on the finite element analysis results, it is known  that damage mechanism  and design fault were caused by yield stress of cross beam that exceededthe material yield strength.Futher, a design improvement  of  cross beam was done by additional structure that can reduce the stress into  safe limits.AbstrakRiset ini fokus pada kerusakan struktur batang lintang yang berfungsi untuk dudukan lengan rem pada kereta makan pada rangkaian kereta api. Analisa kerusakan batang lintang didasarkan pada kondisi desain dan kondisi aktual pemakaianya. Investigasi kerusakan batang lintang dilakukan dengan analisa finite elemen. Berdasarkan pada hasil analisa diketahui faktor penyebab dan mekanisme kerusakan pada batang lintang adalah akibat kesalahan desain yang menyebabkan tegangan melampaui tegangan yield material, selanjutnya dibuat perbaikan desain untuk kereta yang telah diproduksi dengan membuat struktur penguat sehingga tegangan yang terjadi turun pada batas aman. Kata Kunci    : Analisa Kerusakan, Kereta Api, Finite Element, Cross Beam, Beban Eksentrik.  ","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"352 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131573845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ANALISA KEGAGALAN PADA PIPA ULIR DI LINGKUNGAN PERMINYAKAN = FAILURE ANALYSIS OF TUBING-DRILL PIPES UNDER OIL ENVIRONMENT","authors":"Deden Suripto","doi":"10.29122/MKK.V14I2.1662","DOIUrl":"https://doi.org/10.29122/MKK.V14I2.1662","url":null,"abstract":"The a research on the damage of tubing-drill pipes at an oil company, has been carried out. Failure of the component may be caused by many factors including material selection and their mishandling during in service. The objective of this research was to find out the reason of any failure or defects of a material during in, some testing methods were used, namely: visual and dimensions test, strength and hardness tests, macroscopic and microscopic test, the chemical analysis of material test, and SEM/EDS test. The results of proved that there were some corrosive elements such as the Cl and S-2 so that there was a the potential for the occurence of pitting and crevice corrosivation at the end of screws and these will be penetrated into the passivation layers of Fe2O3 that absorb aggressive anions such as Cl - and S-2.Keywords : failure analysis, drill pipe, corrosionAbstrak Penelitian terhadap kerusakan pada pipa ulir pada lingkungan perminyakan ,telah dilakukan. Kegagalan dari suatu komponen dapat disebabkan oleh berbagai macam faktor, mulai dari kesalahan pemilihan material sampai dengan kesalahan operator dalam service-nya. Tujuan penelitian adalah untuk mencari penyebab kegagalan terjadinya cacat pada material tubing setelah dioperasikan. Untuk mengetahui penyebabnya dilakukan analisa kegagalan dengan menggunakan beberapa metode, yaitu: pemeriksan visual dan dimensi, pengujian tarik dan kekerasan, pemeriksaan makroskopis dan mikroskopis, pengujian komposisi kimia bahan, dan pengujian SEM/EDS. Hasil penelitian membuktikan bahwa adanya unsur korosif dalam material seperti CL- dan S-2 sehingga sangat potensial untuk terjadinya serangan korosi sumuran maupun korosi celah kikisan pada ujung ulir dan akan berpenetrasi pada lapisan pasivasi Fe2O3 yang sifatnya mengabsorbsi anion-anion agresif seperti CL- dan S-2Kata kunci : analisis kegagalan, pipa ulir, korosi.","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114458119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pengaruh Persentase Reduksi Warm Rolling Terhadap Sifat Mekanik Paduan Cu-Zn 70/30","authors":"Ayu Rizeki Ridhowati, Eka Febriyanti, Rini Riastuti","doi":"10.29122/mkk.v15i2.3375","DOIUrl":"https://doi.org/10.29122/mkk.v15i2.3375","url":null,"abstract":"Abstract Warm rolling is one of the thermomechanical method has several advantages such as produces high mechanical properties, but does not decrease % elongation and toughness value because partial recrystallization phenomenon that produces micron-sized new grain. This paper reports the results of an investigation carried out on the effects of holding time annealing to mechanical properties Cu-Zn 70/30 alloy. These alloy after homogenization process and quenched in the air then heated to temperature of 300°C, later the heated copper samples are warm rolled at 25%, 30%, and 35% reduction, after that heated at temperature 300°C and held during 120 minutes. Then sample is experienced rewarm rolling with reduction 25%, 30%, and 35%. The results obtained showed that the ultimate tensile strength and yield strength are higher proportional with the increasing of % reduction, their values are 501,1 MPa; 599,3 MPa; later decrease to 546, 5 MPa and to yield strength are 441,8 MPa; 466,1 MPa; then decrease to 458,6 MPa. Moreover hardness value increase proportional with % reduction such as 154 HV; 162 HV; after that decrease to 160 HV While, % elongation decreases inversely proportional with % reduction namely 12,4%; 8,2%; later increase to 11,2 %. It is caused of the partial recrystallization phenomenon as evidenced by the presence micron-sized. Warm rolling merupakan salah satu metode termomekanik yang mempunyai beberapa keuntungan yaitu salah satunya menghasilkan sifat mekanik yang tinggi, namun tidak mengurunkan nilai keuletan karena adanya fenomena rekristalisasi parsial yang menghasilkan butiran baru berbentuk micron. Paper ini menjelaskan tentang hasil penelitian berupa pengaruh persentase reduksi terhadap sifat mekanis paduan Cu-Zn 70/30. Paduan Cu-Zn 70/30 setelah dilakukan proses homogenisasi dan didinginkan di udara lalu dipanaskan ke suhu 300°C, kemudian masing-masing dilakukan warm rolling dengan persentase reduksi sebesar 25%, 30%, dan 35% kemudian ditahan di suhu 300°C dalam waktu 120 menit. Selanjutnya sampel dilakukan rewarm rolling dengan persentase reduksi sebesar 25%, 30%, dan 35%. Hasil penelitian yang dilakukan antara lain nilai kekuatan tarik (UTS dan YS) yang semakin tinggi sebanding dengan peningkatan % reduksi warm rolling yaitu masing-masing untuk nilai UTS sebesar 501,1 MPa; 599,3 MPa; lalu menurun menjadi 546,5 MPa serta untuk nilai kekuatan luluh sebesar 441,8 MPa; 466,1 MPa; lalu menurun menjadi 458,6 MPa. Selain itu, nilai kekerasan meningkat sebanding dengan peningkatan % reduksi warm rolling masing-masing sebesar 154 HV; 162 HV; lalu menurun menjadi 160 HV. Sedangkan persentase elongasi semakin menurun berbanding terbalik dengan peningkatan % reduksi masing-masing sebesar 12,4%; 8,2%; lalu meningkat menjadi 11,2%. Hal tersebut disebabkan karena adanya fenomena rekristalisasi parsial yang dibuktikan dengan kehadiran butir kecil berukuran mikron. Keywords:Cu-Zn 70/30 alloy, warm rolling, anneal, % reduction, mechanical prope","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126277235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pengaruh Perubahan Mikrostruktur Terhadap Perubahan Kekerasan Radiant Tube Yang Telah Beroperasi Sejak 2003","authors":"Laili Novita Sari, Sutarjo","doi":"10.29122/MKK.V16I1.3289","DOIUrl":"https://doi.org/10.29122/MKK.V16I1.3289","url":null,"abstract":"Abstract B2TKS - Sub- Analysis of Damage and residual life has done Remaining Life Assessment to the radiant tube on oil and gas companies from 2003 - 2016. In determining the RLA, it was used graph of the Era Technology where the determination is based on the microstructural changes while there are no literature or research which shows the hardness changing of material ASTM A 213 T5 which occurs during the aging process. Therefore it need to make formulation about the changes of spheriodizationto the chages of hardness of radiant tube material ASTM A 213 T5. By knowing a reasonable decrease in hardness to spheriodization, it was expected to detect the abnormal condition or damage earlier. Based on the examination of metallographic and hardness testing ,is was known that the reduction of hardness occur in proportion to the increase ofsperiodization percentage. In spheriodzation changing of Classification A, B, C the decrease of hardness below 0.7 HB / HB0 while classification D until the next classification,reduction of hardness above 0,7HB / HB0. B2TKS – Sub Bidang Analisa Kerusakan dan umur sisa telah melakukan Remaining Life Assesment pada radiant tube pada perusahaan minyak dan gas bumi dari tahun 2003 – 2016. Dalam penentuan RLAdigunakan grafik dari Era Teknologi dimana penentuannya berdasarkan perubahan struktur mikro sedangkan untuk perubahan kekerasan material belum ada literatur atau penelitianyang menunjukkan tentang perubahan kekerasan pada material ASTM A 213 T5yang terjadi selama proses penuaan. Karena itu dilakukan perumusanperubahan kekerasan terhadap speriodisasi pada tube radiant material ASTM A 213 T5. Dengan mengetahui penurunan kekerasan yang wajar terhadap speriodisasi diharapkan akan mempermudah pendeteksian awal kondisi abnornal atau kerusakan. Berdasarkan pengamatan metalografi dan uji kekerasan diketahui bahwa penurunan kekerasan terjadi secara proporsional dengan peningkatan prosentase spriodisasi. Klasifikasi A, B, C penurunan kekerasan dibawah 0,7 HB/HB0 sedangkan klasifikasi D sampai berikutnya penurunan kekerasan diatas 0,7HB/HB0. Keywords: Hardness, radiant tube, in situ metallography, ASTM A 213 T5  ","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"143 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127489264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Penipisan Pipa Ketel Akibat Elemen Korosif Air","authors":"M. Nusa, Hernadi","doi":"10.29122/MKK.V16I1.3287","DOIUrl":"https://doi.org/10.29122/MKK.V16I1.3287","url":null,"abstract":"Abstract Inspection and testing is done to determine the metallurgical phenomena that occur on the boiler pipes that have been operating several years continuously at a temperature of 560 ° C. The study is also intended to determine the operational feasibility of the pipeline and to avoid undetected damage. Investigation of these pipes is also carried out in the laboratory with micro-structure analysis method, inspection crust, tensile test, bending test, hardness and thickness test. From the analysis of the microstructure, boiler pipes are in condition ferrite pearlite spheroidization with a crust that is thick and contains graphite. In addition, The pipes are attacked by uniform and pitting corrosion. The results of tensile and bending tests are still normal (standard). The hardness test results show significant values compared to the standard, as well as the thickness of the pipe thinning as a result of the corrosion process. Inspeksi dan pengujian dilakukan untuk mengetahui fenomena metalurgis yang terjadi terhadap pipa ketel uap yang sudah beroperasi beberapa tahun secara terus menerus pada suhu 560°C. Penelitian juga dimaksudkan untuk mengetahui kelayakan operasional pipa tersebut dan untuk menghindari terjadinya kerusakan yang tidak terdeteksi. Investigasi pipa-pipa tersebut juga dilakukan di laboratorium dengan metode analisa struktur mikro, pemeriksaan kerak, uji tarik, uji bending, uji kekerasan dan ketebalan. Dari analisa struktur mikro, pipa ketel berada pada kondisi ferrit spheroidisasi perlit dengan lapisan kerak yang cukup tebal serta mengandung grafit. Selain itu juga terjadi serangan korosi merata dan korosi sumuran. Hasil uji tarik dan hasil uji bengkok masih normal (memenuhi standar). Hasil uji kekerasan terjadi penurunan nilai yang signifikan dibanding standar, demikian juga pada ketebalan pipa terjadi penipisan akibat dari adanya proses korosi. Keywords: Boiler pipe, spheroidization, corrosion, thinning. ","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115412836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pengaruh Peningkatan Derajat Deformasi Canai Hangat Terhadap Karakteristik Deformation Band Paduan Cu-Zn 70/30","authors":"Eka Febriyanti, Dedi Priadi, Rini Riastuti","doi":"10.29122/MKK.V16I1.3286","DOIUrl":"https://doi.org/10.29122/MKK.V16I1.3286","url":null,"abstract":"Abstract Cu-Zn 70/30 alloy has properties that is relatively soft, ductile, and easy to perform by cold working. However, cold working has the disadvantage that require equipment which has higher loading capacity to generate strength and higher density thus increasing of machining cost. In addition, strain hardening phenomenon due to cold working process resulted in decreasing of ductility material. Therefore, it is necessary alternative fabrication processes to optimize the mechanical properties of Cu-Zn alloy 70/30 that with the TMCP method. TMCP is metal forming material by providing large and controlled plastic strain to the material. TMCP using the deformation percentage variation that 32.25%, 35.48%, and 38.7% from hot rolled research at 500°C temperature in double pass reversible which performed on Cu-Zn 70/30 plate. By tensile testing using universal testing machine can be seen that the Cu-Zn 70/30 alloy on 32.25% degree of deformation, both of UTS and YS respectively are 505 MPa and 460 MPa. Whereas from examination of thickness and density deformation bands by FE-SEM shows denser and thicker deformation band proportional with increasing of deformation degree.Moreover, the values of tensile strength at the edge of the area and the center is directly proportional to the density and thickness of the deformation band. Paduan Cu-Zn 70/30 memiliki sifat yang relatif lunak, ulet, dan mudah dilakukan pengerjaan dingin. Namun, pengerjaan dingin memiliki kekurangan yaitu membutuhkan peralatan yang memiliki kapasitas pembebanan tinggi untuk menghasilkan kekuatan dan kepadatan tinggi sehingga meningkatkan biaya permesinan. Selain itu, fenomena pengerasan regang akibat proses pengerjaan dingin menghasilkan penurunan keuletan material. Oleh karena itu, diperlukan alternatif proses fabrikasi untuk mengoptimalkan sifat mekanik paduan Cu-Zn 70/30 salah satunya dengan metode TMCP. TMCP merupakan suatu proses perubahan bentuk suatu material dengan cara memberikan regangan plastis yang besar dan terkontrol terhadap material. TMCP dengan menggunakan variasi persentase deformasi sebanyak 32,25%, 35,48%, dan 38,70% dari penelitian canai hangat di suhu 500oC secara double pass reversible dilakukan pada pelat paduan Cu-Zn 70/30. Dengan melakukan pengujian tarik menggunakan mesin uji tarik universal testing machine dapat dilihat bahwa pada material paduan Cu-Zn 70/30 pada derajat deformasi 32,25% menghasilkan nilai UTS dan YS masing-masing sebesar 505 MPa dan 460 MPa. Sedangkan dari hasil pengamatan ketebalan dan kerapatan deformation band menggunakan FE-SEM menunjukkan deformation band yang lebih rapat dan lebih tebal sebanding dengan semakin meningkatnya derajat deformasi. Selain itu, nilai kekuatan tarik pada daerah tepi dan tengah berbanding lurus dengan kerapatan dan ketebalan deformation band. Keywords: 70/30 Cu-Zn alloy, warm rolled, deformation degree, deformation bands ","PeriodicalId":398388,"journal":{"name":"Material Komponen dan Konstruksi","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128306754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}