The Microstructure of 100CrMnSi6-4 Steel after Laser Hardening

2014 ◽  
Vol 604 ◽  
pp. 32-35
Author(s):  
Wojciech Napadłek
Keyword(s):  
Radiation Power ◽  
Friction Pair ◽  
Roller Bearing ◽  
Laser Hardening ◽  
Superficial Zone ◽  
Large Size ◽  
Micro Cracks ◽  
High Microhardness ◽  
Technological Opportunities ◽  
Geometric Surface

This paper presents analysis of the influence of the laser hardening bearing 100CrMnSi6-4 steel on the selected properties: hardness and microstructure. The best process parameters were selected by: radiation impulse length λ = 1064 nm, different radiation power density and repetition frequency, as well as different variants of geometric surface texture. The process was carried out in a air environment, mainly in the field of ablation texturing with "thermal effect." As a result of laser hardening, the obtained martensitic microcrystalline microstructure in the superficial zone and in the middle of the hardened zone, and martensitic - bainite and bainite in the transition zone. The microstructures with high microhardness in the range of 580 850 HV0.01 are resulting from ultrafast phase transformation occurring during the crystallization of the Fe-C-Cr-Mn-Si alloy from the liquid phase. The microstructures are in the area directly adjacent to the lubricant microchannels produced during laser texturing. It was clearly noticeable on highly fragmented microstructure and confirmed by increased microhardness. There were no micro-cracks on the surface layer, what promises great technological opportunities. The results are promising and may have a significant impact on improving the tribological associations friction pair: roller - large-size track roller bearing.

The Surface Stereometry and Microstructure of Steel 100CrMnSi6-4 after Ablation Laser Texturing

2014 ◽  
Vol 604 ◽  
pp. 41-44
Author(s):  
Wojciech Napadłek ◽  
Zdzisław Bogdanowicz ◽  
Wojciech Chrzanowski ◽  
Artur Król
Keyword(s):  
Cross Sections ◽  
Roller Bearing ◽  
Bearing Steel ◽  
Laser Texturing ◽  
Texture Characteristic ◽  
Micro Cracks ◽  
Ablation Laser ◽  
Core Hardness ◽  
Hardness Increase ◽  
Geometric Surface

Publication presents an analysis of possibility of applying ablation laser texturing of 100CrMnSi6-4 bearing steel in the tribological aspect. Selection of different variants of laser micromachining, including pulsed radiation (λ=1.064 μm), and different variants of geometric surface texture, characteristic surface stereometry was obtained with regular arranged lubrication microchannels on the surface roller bearing steel. Maximal hardness in the melted and laser hardened zone, inside the micro-container and in its nearby zone, increased up to 800÷1000 HV0.05 (about 60÷75% increase) in comparison to the core hardness (610÷660 HV0.05). Local hardness increase even up to 1100 HV0.05 was noticed. No micro-cracks in the surface layer neither in the lubricant micro-containers were found. Moreover, no material degradation in the cross-sections in the micro-containers was noticed.

Research of the kinetics of thickness of the boundary layers of lubricating materials applied to drilling technology

2021 ◽  
pp. 115-120
Author(s):  
R.A. Ismakov ◽  
◽  
V.G. Konesev ◽  
F.N. Yangirov ◽  
G.L. Gaymaletdinova ◽  
...  
Keyword(s):  
Service Life ◽  
Boundary Layers ◽  
Friction Pair ◽  
Roller Bearing ◽  
Equipment Safety ◽  
Efficiency And Effectiveness ◽  
Drilling Technology ◽  
Resource Characteristics ◽  
Friction Surfaces ◽  
Kinetics Of

Improving the operational properties of lubricants increases the service life of the mechanisms and increase the durability of rubbing joints, which has a positive effect on the indicators of technical and economic efficiency and equipment safety. Therefore, great attention in tribology is paid to the analysis of the state of friction units in technology and the assessment of their resource characteristics, which makes it possible to increase their service life. The research aim is to study the general provisions on lubricants and lubricants, as well as the features of the boundary layers formation on friction surfaces and the observed patterns. Calculations of the boundary layers thickness using lubricating reagents at different energetic loading of the friction pair were carried out as applied to the roller bearing of a roller cone bit in the medium of cylinder oil 52 and DPS grease. The proposed research methodology made it possible to in-crease the efficiency and effectiveness of the means development for improving the tribotech-nical properties of drilling lubricants.

scholarly journals Possibilities of precision material micro-processing by laser pulse copper-vapor radiation

2017 ◽  
Vol 2 (2) ◽  
pp. 36-48
Author(s):  
Мишик Казарян ◽  
Mishik Kazaryan ◽  
Николай Лябин ◽  
Nikolay Lyabin ◽  
Александр Григорьянц ◽  
...  
Keyword(s):  
Radiation Power ◽  
Sheet Material ◽  
Thin Sheet ◽  
Visible Spectrum ◽  
Copper Vapor ◽  
Micro Cracks ◽  
Thin Sheet Material ◽  
Spectrum Region ◽  
Experimental Researches

The paper reports the results of experimental researches on microprocessing by laser copper-vapor radiation with wave-lengths of radiation in the visible spectrum region of 510.6 and 578.2 nm and the frequency of pulse repetition of 14-15kHz, a nano-second duration of pulses and a peak power density of 109-1011 W/cm2 in the focused spot light with the diameter of 10…20µkm. The investigations carried out became a basis for the creation of modern automated laser technological plants “Caravelle-2” and “Caravelle-2M” and with the average radiation power of 6-8W, an operation field of horizontal XY- table 100x100 and 200x200mm and positioning accuracy on axes ±2µkm for the precision micro-machining of foil materials – 0.01-0.2mm; “Caravelle-1” and “Caravelle-1M” with the radiation power of 10-15 20-25 W, an operation field of XY-table 150x150mm for the thin-sheet material micro-processing – 0.3-0.5mm and 0.6-1mm. The productivity of the plants mentioned as compared with common methods including also EEM is by an order and more higher. Material micro-processing with laser nano-second copper-vapor radiation ensures a higher quality of a cut: minor roughness of a cut surface (≥1…3µkm) and the area of thermal impact (≤3…5µkm) and stratifications and micro-cracks do not appear in such heat-resistant material as molybdenum and tungsten.

scholarly journals Assessment of friction pair elements condition based on changes in the geometric surface structure isotropicity degree

2019 ◽  
Vol 302 ◽  
pp. 01015 ◽  
Author(s):  
Maciej Matuszewski ◽  
Małgorzata Słomion ◽  
Adam Mazurkiewicz ◽  
Danil Yu. Pimenov
Keyword(s):  
Weight Loss ◽  
Surface Layer ◽  
Surface Structure ◽  
Friction Pair ◽  
Tribological Characteristics ◽  
Roughness Parameters ◽  
Functional Characteristics ◽  
Tribological Tests ◽  
Functional Features ◽  
Geometric Surface

This paper regards the possibility of using the degree of the surface isotropicity to assess the condition of the surface layer friction pair elements. The analysis is based on certain changes in operational and technological surface layer. The methods of constituting the surface layer have been characterized due to the features of geometric surface structure as well as the problem of assessing the condition of surface in terms of functional features and tribological characteristics. The evaluation of the occurring changes in the surface layer have been conducted by performing tribological tests and for descript condition of surfaces the degree of surface isotropicity and weight loss of specimens have been adopted. Whereas the assessment of technological state of the surface layer has been carried out for the surface after its coating. Based on the analysis, it has been found that the use for assessment the condition of surface layer and the degree of the surface isotropicity are useful and it is an alternative way or supplement to classical adoption of a properly selected set of roughness parameters to evaluate the potential functional characteristics of friction couples surfaces.

Investigation of the Laser-Powder Cladding Effect on Steel Surface Hardening

2015 ◽  
Vol 788 ◽  
pp. 52-57
Author(s):  
Valeriy V. Krasheninnikov ◽  
Аleksandr G. Malikov ◽  
Аnatolii M. Orishich ◽  
Аleksandr O. Tokarev
Keyword(s):  
Carbon Steel ◽  
Radiation Power ◽  
Low Carbon Steel ◽  
High Hardness ◽  
Spring Steel ◽  
Laser Hardening ◽  
Low Carbon ◽  
Surface Alloying ◽  
Steel 20 ◽  
Heating Up

The investigation was carried out in the laser-technological complex with the power up to 8 kW, ITAM SB RAS. An inert-gas jet was supplied coaxially with the beam. A protective nozzle from which gaseous Ar was injected was used to protect the hardening joint. The parameters of the laser hardening process with the surface alloying was optimized on the samples of low-carbon steel 20, construction steel 45, and spring steel 65G.Special cladding powders containing carbon, manganese, nickel, chromium, molybdenum, tungsten, silicon, boron, and nitrogen were chosen for laser-powder cladding. They are intended for cladding wear-resistant layers onto machine parts, tools and equipment operated under abrasion-wear conditions with moderate shock loading.It was found that an optimal radiation power was 2 kW. Extra water cooling of treated parts is unpractical during laser hardening because it did not improve the hardening effect. The best effect of surface alloying was reached when the powder of rapid tool steel Р6М5 was injected in the liquid metal pool. High hardness of the clad layer remained at further heating up to 550°C. The use of laser thermal treatment and laser-powder cladding provides thermal hardening and enables increasing hardness and hence wear resistance of low-carbon steel parts by 3 - 4 times, whereas the base part remains viscous.

Study on Ultrasonic Test Defects Causes of Medium Plate

2011 ◽  
Vol 194-196 ◽  
pp. 259-262 ◽  
Author(s):  
Yong Li Chen ◽  
Hui Yan ◽  
Bin Hu ◽  
Shu Yan Ren ◽  
Rao Chuang Liu ◽  
...  
Keyword(s):  
Defect Detection ◽  
Steel Surface ◽  
Surface Defects ◽  
Ultrasonic Test ◽  
Alloying Elements ◽  
Matrix Composition ◽  
Large Size ◽  
Micro Cracks ◽  
The Matrix ◽  
Object Of Study

In this paper,Q345E steel as the object of study,analysis of several typical internal defects of UST to explore the reasons for failure caused by UST testing.The results show that: the center segregation of Mn/S is likely to induce center segregation structure of P+B with a whole cleaning micro-cracks,large size spherical oxide of Si/Ca is an important incentive for causing micro-cracks;Billet board defect detection defect likely to cause an important reason;crack at the alloying elements sharply higher than the matrix composition.Billet defects is an important reason to cause steel surface defects；the alloying elements in place nearing the crack sharply higher than the matrix composition.

Radial Clearance is Key Factor Affecting Roller Bearing Life Prediction in Tri-Cone Bit

2008 ◽  
Vol 44-46 ◽  
pp. 233-238
Author(s):  
Chang Gen Bu
Keyword(s):  
Heat Treatment ◽  
Mathematical Model ◽  
Contact Stress ◽  
Life Prediction ◽  
Friction Pair ◽  
Roller Bearing ◽  
Radial Clearance ◽  
Bearing Life ◽  
Key Factor

The life of tri-cone bits will directly affect the economic and technical drilling target. In order to control and evaluate bit’s life, the paper builds up the calculating mathematical model, which is suitable for determination of tri-cone bit’s life, to rationally design the radial clearance of non standard bearings. Effect of the radial clearance on the life of roller bearing was systematically deduced. The larger the radial clearance is; the higher the contact stress is; and the shorter the roller bearing life is. It follows from the model that the key factor of the radial clearance should be taken into consideration besides structure data and anti-friction pair’s heat treatment of roller bearing in order to decrease the contact stress of anti-friction pair and prolong the bit’s life.

Coherency loss in γ' precipitates in nickel-base superalloy

1983 ◽  
Vol 41 ◽  
pp. 244-245
Author(s):  
R. A. Ricks ◽  
Angus J. Porter
Keyword(s):  
Lattice Mismatch ◽  
Lattice Parameter ◽  
Nickel Base Superalloy ◽  
Large Size ◽  
The Matrix ◽  
Nimonic 80A ◽  
Interfacial Dislocations ◽  
Nickel Base ◽  
Coherency Loss ◽  
Nimonic 115

During a recent investigation concerning the growth of γ' precipitates in nickel-base superalloys it was observed that the sign of the lattice mismatch between the coherent particles and the matrix (γ) was important in determining the ease with which matrix dislocations could be incorporated into the interface to relieve coherency strains. Thus alloys with a negative misfit (ie. the γ' lattice parameter was smaller than the matrix) could lose coherency easily and γ/γ' interfaces would exhibit regularly spaced networks of dislocations, as shown in figure 1 for the case of Nimonic 115 (misfit = -0.15%). In contrast, γ' particles in alloys with a positive misfit could grow to a large size and not show any such dislocation arrangements in the interface, thus indicating that coherency had not been lost. Figure 2 depicts a large γ' precipitate in Nimonic 80A (misfit = +0.32%) showing few interfacial dislocations.

Automatic analysis of Kikuchi diffraction patterns

1994 ◽  
Vol 52 ◽  
pp. 900-901
Author(s):  
H. Weiland ◽  
D. P. Field
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Spatial Resolution ◽  
Relevant Information ◽  
Crystalline Materials ◽  
Large Size ◽  
Transmission Electron ◽  
New Type ◽  
Diffraction Patterns ◽  
Orientation Determination

Recent advances in the automatic indexing of backscatter Kikuchi diffraction patterns on the scanning electron microscope (SEM) has resulted in the development of a new type of microscopy. The ability to obtain statistically relevant information on the spatial distribution of crystallite orientations is giving rise to new insight into polycrystalline microstructures and their relation to materials properties. A limitation of the technique in the SEM is that the spatial resolution of the measurement is restricted by the relatively large size of the electron beam in relation to various microstructural features. Typically the spatial resolution in the SEM is limited to about half a micron or greater. Heavily worked structures exhibit microstructural features much finer than this and require resolution on the order of nanometers for accurate characterization. Transmission electron microscope (TEM) techniques offer sufficient resolution to investigate heavily worked crystalline materials.Crystal lattice orientation determination from Kikuchi diffraction patterns in the TEM (Figure 1) requires knowledge of the relative positions of at least three non-parallel Kikuchi line pairs in relation to the crystallite and the electron beam.

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