The Study of the Formation Process of Microstructure and Properties during Laser Alloying of the Surface of the Structural Steels

2021 ◽  
Vol 1037 ◽  
pp. 442-448
Author(s):  
G.N. Gavrilov ◽  
Evgeny A. Marinin ◽  
Pavel M. Yavtushenko ◽  
Nikolay S. Uglov ◽  
Kseniya V. Razheva

Development and implementation of new methods of high-energy surface treatment of structural steels is one of the priorities of modern materials science One of the urgent problems of power engineering is the development of effective processing technologies that allow parts to provide the required properties of working surfaces. The use of laser technologies helps to increase wear resistance, corrosion resistance, reduce the duration of chemical and thermal treatment time and other technological characteristics that can improve the quality, durability and efficiency of parts, increase economic and environmental effects.

2014 ◽  
Vol 891-892 ◽  
pp. 1639-1644 ◽  
Author(s):  
Kazutaka Mukoyama ◽  
Koushu Hanaki ◽  
Kenji Okada ◽  
Akiyoshi Sakaida ◽  
Atsushi Sugeta ◽  
...  

The aim of this study is to develop a statistical estimation method of S-N curve for iron and structural steels by using their static mechanical properties. In this study, firstly, the S-N data for pure iron and structural steels were extracted from "Database on fatigue strength of Metallic Materials" published by the Society of Materials Science, Japan (JSMS) and S-N curve regression model was applied based on the JSMS standard, "Standard Evaluation Method of Fatigue Reliability for Metallic Materials -Standard Regression Method of S-N Curve-". Secondly, correlations between regression parameters and static mechanical properties were investigated. As a result, the relationship between the regression parameters and static mechanical properties (e.g. fatigue limit E and static tensile strength σB) showed strong correlations, respectively. Using these correlations, it is revealed that S-N curve for iron and structural steels can be predicted easily from the static mechanical properties.


2010 ◽  
Vol 1 (SRMS-7) ◽  
Author(s):  
David Pennicard ◽  
Heinz Graafsma ◽  
Michael Lohmann

The new synchrotron light source PETRA-III produced its first beam last year. The extremely high brilliance of PETRA-III and the large energy range of many of its beamlines make it useful for a wide range of experiments, particularly in materials science. The detectors at PETRA-III will need to meet several requirements, such as operation across a wide dynamic range, high-speed readout and good quantum efficiency even at high photon energies. PETRA-III beamlines with lower photon energies will typically be equipped with photon-counting silicon detectors for two-dimensional detection and silicon drift detectors for spectroscopy and higher-energy beamlines will use scintillators coupled to cameras or photomultiplier tubes. Longer-term developments include ‘high-Z’ semiconductors for detecting high-energy X-rays, photon-counting readout chips with smaller pixels and higher frame rates and pixellated avalanche photodiodes for time-resolved experiments.


2021 ◽  
Vol 410 ◽  
pp. 469-474
Author(s):  
Ivan S. Safronov ◽  
Alexander I. Ushakov

One of the most important purposes of materials science is the ability to govern the physical properties of materials characterized by different structures. The strength properties of nanostructured metal alloys do not always meet the exploitation requirements. The set of properties of such materials is stable within narrow limits: temperature, mechanical, and corrosion conditions. Traditional processing modes are ineffective for such materials. Attempts to use them often lead to the loss of unique physical and chemical properties. The most effective methods of processing such materials are associated with the use of laser radiation. The laser pulse has a number of features, including a complex effect on the surface layers of the material. Spot and short irradiation with high-energy rays can preserve the unique physical properties of samples as a whole and improve strength indicators without destroying the structure of the material as a whole.


Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 880 ◽  
Author(s):  
Yanhua Yao ◽  
Nannan Zhang ◽  
Xiao Liu ◽  
Qiaofeng Dai ◽  
Haiying Liu ◽  
...  

In this paper, the plasmon resonance effects of gold nanorods was used to achieve rapid photothermal therapy for malignant melanoma cells (A375 cells). After incubation with A375 cells for 24 h, gold nanorods were taken up by the cells and gold nanorod clusters were formed naturally in the organelles of A375 cells. After analyzing the angle and space between the nanorods in clusters, a series of numerical simulations were performed and the results show that the plasmon resonance coupling between the gold nanorods can lead to a field enhancement of up to 60 times. Such high energy localization causes the temperature around the nanorods to rise rapidly and induce cell death. In this treatment, a laser as low as 9.3 mW was used to irradiate a single cell for 20 s and the cell died two h later. The cell death time can also be controlled by changing the power of laser which is focused on the cells. The advantage of this therapy is low laser treatment power, short treatment time, and small treatment range. As a result, the damage of the normal tissue by the photothermal effect can be greatly avoided.


Author(s):  
Ruslan Kisilyov ◽  
◽  
Vasil Khmelevsky ◽  
Petro Luzan ◽  
Iryna Sysolina ◽  
...  

Improving of livestock industry efficiency significantly depends on quality of feed preparation, as they are in cost structure of products are 30-60% of costs. Advanced technologies that allow to fully realize genetic potential of animals, due to the lack of necessary technical support have not become widespread. The experience of using intensive full-system technologies for livestock production shows that, along with reliable and balanced provision of farms with high quality feeds, traditional feeding systems are being improved, which are aimed at the development of economically efficient mechanized feed processing technologies and the preparation of full-range and balanced feed mixtures. Existing designs of feed mixers for cattle do not fully meet the zootechnical requirements for the preparation of multicomponent balanced complete feed mixtures, have high energy costs and high specific material consumption. Therefore, research aimed at developing working bodies for feed mixers, which will ensure the creation of a highly efficient feed base at low energy and material costs are of economic importance and is an urgent scientific task. In the article on the basis of the conducted researches the basic constructive-technological scheme of the effective single-shaft two-section mixer for realization of process of preparation of balanced mixes for cattle executed in the form of the horizontally located cylindrical case with the combined mixer consisting of section of screw tapes and flat blades (left and right) direction of inclination, the working surface of which is located at an angle of 45… 500 to the axis of the shaft and is equipped with radial fingers. The purpose of experimental research was to establish identification of developed mathematical models and adequacy of research results of proposed feed mixer and determine impact of basic parameters and modes of its operation on quality process. Аchieve this goal, mutual influence of simultaneous changes in speed of agitator shaft, width of flat blade angle of blade to axis of agitator shaft and duration of feed mixing on quality process: homogeneity of mixture and drive power of mixer shaft. Theoretical studies of the process of preparation of a balanced complete ration mixture confirmed the advantage of the developed design of the combined two-section mixer and increased the quality index (homogeneity of the mixture) to 98%


2013 ◽  
Vol 772 ◽  
pp. 57-61 ◽  
Author(s):  
Norbert Schell ◽  
Andrew King ◽  
Felix Beckmann ◽  
Torben Fischer ◽  
Martin Müller ◽  
...  

The HEMS beamline at PETRA III has a main energy of 120 keV, is tunable in the range 30-200 keV, and optimized for sub-micrometer focusing with Compound Refractive Lenses. Design, construction, and main funding was the responsibility of the Helmholtz-Zentrum Geesthacht, HZG. Approximately 70 % of the beamtime is dedicated to Materials Research, the rest reserved for “general physics” experiments covered by DESY, Hamburg. The beamline P07 in sector 5 consists of an undulator source optimized for high energies, a white beam optics hutch, an in-house test facility and three independent experimental hutches, plus additional set-up and storage space for long-term experiments. HEMS has partly been operational since summer 2010. First experiments are introduced coming from (a) fundamental research for the investigation of the relation between macroscopic and micro-structural properties of polycrystalline materials, grain-grain-interactions, recrystallisation processes, and the development of new & smart materials or processes; (b) applied research for manufacturing process optimization benefitting from the high flux in combination with ultra-fast detector systems allowing complex and highly dynamic in-situ studies of microstructural transformations, e.g. in-situ friction stir welding; (c) experiments targeting the industrial user community.


Membranes ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 163 ◽  
Author(s):  
Casimiro ◽  
Ferreira ◽  
Leal ◽  
Pereira ◽  
Monteiro

The use of ionizing radiation processing technologies has proven to be one of the most versatile ways to prepare a wide range of membranes with specific tailored functionalities, thus enabling them to be used in a variety of industrial, environmental, and biological applications. The general principle of this clean and environmental friendly technique is the use of various types of commercially available high-energy radiation sources, like 60Co, X-ray, and electron beam to initiate energy-controlled processes of free-radical polymerization or copolymerization, leading to the production of functionalized, flexible, structured membranes or to the incorporation of functional groups within a matrix composed by a low-cost polymer film. The present manuscript describes the state of the art of using ionizing radiation for the preparation and functionalization of polymer-based membranes for biomedical and environmental applications.


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