Materiali in tehnologije最新文献_第8页

EFFECT OF A SCANDIUM ADDITION ON ANODIZING AlMg ALLOYS 添加钪对铝合金阳极氧化的影响

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-03-30 DOI: 10.17222/mit.2023.755

B. Karpe, Katarina Kern, J. Kovač, M. Klanjšek Gunde, A. Nagode, M. Bizjak, M. Zorc

{"title":"EFFECT OF A SCANDIUM ADDITION ON ANODIZING AlMg ALLOYS","authors":"B. Karpe, Katarina Kern, J. Kovač, M. Klanjšek Gunde, A. Nagode, M. Bizjak, M. Zorc","doi":"10.17222/mit.2023.755","DOIUrl":"https://doi.org/10.17222/mit.2023.755","url":null,"abstract":"Scandium (Sc) is known to be one of the most effective alloying elements of aluminum alloys. The only drawback is its high price, but that could change quickly due to the promising results of recent research on its extraction. However, the data on how it affects anodic oxidation are very scarce. In this research, we analyzed how a micro-addition of Sc to the AlMg alloy affects the growth mechanism and properties of the protective aluminium oxide layer depending on the anodization parameters. For comparison, alloy AA5083 with a similar magnesium content was also anodized with the same anodizing parameters. In all experiments, sulfuric acid (VI) with concentrations of 1.72 M or 2.2 M at temperatures of 21 °C or 35 °C was used as the electrolyte. Potentiostatic (18 V) and galvanostatic (20 mA/cm2) anodizing methods were applied. The results (SED-EDS) show that scandium is uniformly intercalated in the matrix of the oxide layer and decreases its resistivity, which increases the oxide growth rate during potentiostatic anodizing and decreases the pore density and pore diameters during galvanostatic anodizing. Moreover, it increases the mobility of cations through the oxide layer, thus accelerating the oxidation reaction in concentrated sulfuric acid electrolytes. On the other hand, the increased cation mobility considerably increases the sensitivity to the temperature of the electrolyte, which can change the growth mechanism of the oxide layer and thus its morphology.","PeriodicalId":18258,"journal":{"name":"Materiali in tehnologije","volume":"11 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72846552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

MECHANICAL AND METALLURGICAL PROPERTIES OF FRICTION-STIR-WELDED AISI 304 STAINLESS STEEL aisi 304不锈钢摩擦搅拌焊接的力学和冶金性能

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-03-30 DOI: 10.17222/mit.2022.678

Sundar raju Govindaraj, Sivakumar Karuppa

{"title":"MECHANICAL AND METALLURGICAL PROPERTIES OF FRICTION-STIR-WELDED AISI 304 STAINLESS STEEL","authors":"Sundar raju Govindaraj, Sivakumar Karuppa","doi":"10.17222/mit.2022.678","DOIUrl":"https://doi.org/10.17222/mit.2022.678","url":null,"abstract":"Friction stir welding of AISI 304 stainless-steel sheets was successfully carried out with a tungsten-alloy (W+La2O3) tool and the effect of the tool rotational speed on the microstructure and mechanical properties of the joints were evaluated. 3-mm-thick plates were friction-stir welded at various rotational speeds of 600–1000 min–1 and a constant welding speed of 40 mm/min with a constant axial load of 15 kN. Defect-free joints were produced at 800 min–1 and 900 min–1, indicating a proper plastic flow of the material and ensuring adequate heat generation during welding. Tensile, Charpy impact, compression and microhardness tests were performed to evaluate the joint mechanical properties. The microstructural behavior of the welded and base-metal samples was examined with optical microscopy and scanning electron microscopy. According to the mechanical results, the welded material has a higher yield strength than the base metal due to the grain refinement and work hardening effect in the stir zone. FSW welds have a higher hardness than the base metal due to the high density of dislocations and continuous dynamic recrystallization. The joints also exhibit acceptable impact toughness. Finally, the EDS analysis confirms that there is no secondary-phase formation in the weld zone of the fabricated material.","PeriodicalId":18258,"journal":{"name":"Materiali in tehnologije","volume":"41 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81273118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

EFFECT OF THICKNESS REDUCTIONS ON MICROSTRUCTURE AND NANO-MECHANICAL PROPERTIES OF AZ31 MAGNESIUM ALLOY IN FLOW-FORMING 减薄对az31镁合金流动成形组织和纳米力学性能的影响

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-01-25 DOI: 10.17222/mit.2022.659

Han Zhang, Tingting Zhang, J. Zhang, Zhihang Yan, Wen-xian Wang

引用次数: 0

INVESTIGATION OF THE SURFACE QUALITY OF AA6082-ZrO2-Gr MMCs USING ABRASIVE WATERJET MACHINING 磨料水射流加工AA6082-ZrO2-Gr复合材料表面质量的研究

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-01-25 DOI: 10.17222/mit.2022.602

Kannapiran Karuppasamy, B. Ranganathan

引用次数: 0

A SINGLE-LAYER FSS FOR S-, C-, X-, KU- AND K-BAND APPLICATIONS 单层FSS，适用于s -， c -， x -， ku -和k -波段应用

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-01-25 DOI: 10.17222/mit.2022.710

Srigitha Surendranath, Varalakshmi Subramanian, Arthi Devarani Paulretnam, Elakkiya Azhagar

引用次数: 0

PREPARATION AND HARDNESS OF A FUNCTIONALLY GRADED Ni-Al COATING 一种功能梯度镍铝涂层的制备及其硬度

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-01-25 DOI: 10.17222/mit.2022.650

Ningning Li, Lei Xu, Liang Huang, Yuping Tong, Z. Jiang, Keliang Li

引用次数: 0

EFFECTS OF PRE-OXIDATION ON HOT CORROSION RESISTANCE OF Al–Si COATINGS 预氧化对铝硅涂层耐热腐蚀性能的影响

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-01-25 DOI: 10.17222/mit.2022.689

R. Palanivel, Soundararaja Perumal Vigneshwaran, Y. Alqurashi, M. A. Rasheed

引用次数: 0

AUSCULTATION OF A HEART AND VASCULAR ACTIVITY DURING AURICULAR NERVE STIMULATION 听诊在耳神经刺激时对心脏和血管活动的听诊

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-01-25 DOI: 10.17222/mit.2022.700

P. Pečlin, J. Rozman, Renata Janež, Nuša Bajželj, S. Ribaric, T. Mirkovic̆

{"title":"AUSCULTATION OF A HEART AND VASCULAR ACTIVITY DURING AURICULAR NERVE STIMULATION","authors":"P. Pečlin, J. Rozman, Renata Janež, Nuša Bajželj, S. Ribaric, T. Mirkovic̆","doi":"10.17222/mit.2022.700","DOIUrl":"https://doi.org/10.17222/mit.2022.700","url":null,"abstract":"The principal objective of the research was to develop and test a multichannel system intended to capture heart (PCG) and Korotkoff sound (KS) signals in a human model of transcutaneous auricular nerve stimulation (tANS). In particular, the purpose was to develop contact auscultation transducers (transducers) capable of capturing PCG and KS at standard auscultation positions without and during the selective tANS. The scope was to develop transducers capable of capturing body sounds lying in a portion of the frequency spectrum between 20 Hz and 200 Hz. They should be as insensitive as possible to external sound or ambient noise and should be capable of compensating for friction noise due to body movements. The system developed consisted of five transducers, where four of them were intended for the auscultation of PCG generated by heart valves, while one of them was intended to capture KS. The functionality of the transducers was tested in the female model by applying four of transducers to the standard positions on the chest and one over the Brachial artery. The results show that the system developed was highly sensitive to PCG and KS, and less sensitive to external ambient sounds and friction noise. Namely, the S1 and S2 heart-sound peaks are present clearly in the recorded PCG signal as well as during the tANS. It was also shown that during the tANS, heart cycles became slightly shorter and, thus, the heart rhythm slightly higher. Finally, during the tANS, both heart sounds S1 and S2 became louder. In conclusion, the findings provide some evidence that the sounds captured by the transducers emanate from the organs under study and are related to their activity and tANS.","PeriodicalId":18258,"journal":{"name":"Materiali in tehnologije","volume":"105 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86965718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

SHRINKAGE BEHAVIOR OF AN ECO-FRIENDLY ENGINEERED CEMENTITIOUS COMPOSITE 一种环保工程胶凝复合材料的收缩特性

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-01-25 DOI: 10.17222/mit.2022.669

R. R. Infanto, S. A. Kumar

引用次数: 0

ADVANCED MATERIALS AND RESEARCH FOR THE GREEN FUTURE 绿色未来的先进材料和研究

IF 0.5 4区材料科学

Materiali in tehnologije Pub Date : 2023-01-25 DOI: 10.17222/mit.2022.717

B. Podgornik

{"title":"ADVANCED MATERIALS AND RESEARCH FOR THE GREEN FUTURE","authors":"B. Podgornik","doi":"10.17222/mit.2022.717","DOIUrl":"https://doi.org/10.17222/mit.2022.717","url":null,"abstract":"Environmental concerns, such as pollution, greenhouse-gas emissions, sustainability, global warming and climate change, are the biggest challenges of our times. In this respect, the more efficient use of energy and materials combined with technology optimization and innovation are playing a key role in the quest to become a green society with green industry. Multiple environmental and economic benefits can mostly be achieved through novel, lightweight energy-efficient designs. In order to develop and properly use new materials and new designs, complete understanding and information on their properties must be obtained. It is also vital to know how these properties are affected by the conditions of a specific application. Furthermore, as the design of components is pushed towards the limits, unsuitable and outdated measuring methods, measuring uncertainty and deviations from the defined material properties can lead to unexpected premature failure of the component and environmental problems. \u0000For the green future, it is extremely important to develop new, advanced materials. However, it is often the changes of the production technology and to the surface of an already-existing material that can achieve great benefits to performance as well as the environment. It is all about modifying the material to perform better, last longer, be biocompatible and achieve different functionalities. Finally, besides high-tech equipment and research facilities, close cooperation between universities, research institutes and industry is needed to develop technologies, functional materials and solutions that can effectively support the journey of our society into a green future","PeriodicalId":18258,"journal":{"name":"Materiali in tehnologije","volume":"29 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81384075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0