Dynamic Behavior of All-Ceramic Spindle-Bearing Unit with Preload

2013 ◽  
Vol 365-366 ◽  
pp. 314-317
Author(s):  
Song Hua Li ◽  
Xue Li ◽  
Ming Hao Feng ◽  
Yu Hou Wu ◽  
Xiao Lin Jin
Keyword(s):  
Natural Frequency ◽  
High Speed ◽  
High Hardness ◽  
The Finite Element Method ◽  
Analysis Model ◽  
Engineering Ceramics ◽  
Bearing Unit ◽  
Spindle Bearing ◽  
Low Thermal Expansion ◽  
All Ceramic

Abstract. Because of the extraordinary physical properties of engineering ceramics such as high hardness, low thermal expansion, light weight and abrasion resistant, it accommodates very well with the high-speed and precision requirements of spindle-bearing unit. In order to prove the superior dynamic characteristic of the all-ceramic spindle-bearing unit bacause of the application of engineering ceramics in shaft and bearing of spindle system, the natural frequency and modes of the all-ceramic spindle-bearing unit were analyzed. In this study, spindle-bearing model was built and analyzed by the Finite Element Method(FEM) and Hertz theory, comprehensively considering both of the stiffness of bearing and the effect of preload, which was different from the tranditional spindle analysis model. The research results show that all-ceramic spindle-bearing unit has higher natural frequency and better dynamic characteristics compare of traditional steel spindle-bearing unit.

Research on Optimal Design and Processing of High-Speed Ceramic Ball Bearings without Inner Rings

2013 ◽  
Vol 446-447 ◽  
pp. 513-517 ◽  
Author(s):  
Song Hua Li ◽  
Ming Hao Feng ◽  
Yu Hou Wu
Keyword(s):  
Optimal Design ◽  
High Speed ◽  
Performance Test ◽  
Advanced Manufacturing ◽  
Ceramic Bearing ◽  
Spindle Bearing ◽  
Low Thermal Expansion ◽  
External Point ◽  
All Ceramic ◽  
Modern Machine

Under the background that modern machine tools have higher requirements to the spindle system, the accuracy, stiffness, critical speed and dynamic stability of the spindle bearing also put forward higher requirements. Traditional steel spindle has been difficult to meet the needs, because of its inherent characteristics. Advanced ceramics have excellent performance, such as low density, low thermal expansion coefficient, high stiffness, wear resistance and good chemical and thermal stability, which can meet the requirements of modern machine tool spindle to the performance of bearing material. The longest fatigue life is the objective function, the calculation method of the ceramic bearing optimal design is the external point method of penalty function, and the all-ceramic bearings without inner rings are successfully manufactured by the advanced manufacturing technology. Finally, the high-speed ceramic motorized spindle prototype was assembled with high precision successfully, and its performance test and analysis were finished, the results show that using the all-ceramic bearing can effectively improve the rotation accuracy and rotational stiffness of the spindle-bearing system.

Dynamics of Spindle-Bearing Systems at High Speeds Including Cutting Load Effects

1998 ◽  
Vol 120 (2) ◽  
pp. 387-394 ◽  
Author(s):  
Bert R. Jorgensen ◽  
Yung C. Shin
Keyword(s):  
Natural Frequency ◽  
High Speed ◽  
Dynamic Models ◽  
Complex Geometry ◽  
Beam Theory ◽  
Coupled System ◽  
Influence Coefficient ◽  
High Speeds ◽  
Spindle Bearing ◽  
Influence Coefficient Method

Increased use of high speed machining creates the need to predict spindle-bearing performance at high speeds. Previous spindle-bearing models simplify either spindle or bearing dynamics to the extent of prohibiting a detailed analysis of a spindle with high speed motion. At high speeds, centrifugal loading in the bearing causes stiffness softening, creating a change in natural frequency. Therefore, spindle modeling requires a comprehensive representation of the dynamics of shafts with complex geometry rotating at high speeds and supported by non-linear bearings. This paper presents a coupled system of spindle and bearing dynamic models with numerical solution. Spindle dynamics are modeled using the influence coefficient method of discrete lumped masses, based on Timoshenko beam theory. Both linear and rotational bearing stiffness are included in the spindle model through solution of the angular-contact bearing model. The parameters of cutting loads, tool mass, and rotational speed are analyzed, and all are shown to affect the natural frequency. The computer model is both rapid and robust, and shows excellent agreement with experimental analysis.

Research on Application of Advanced Ceramics in Machine Tool Spindles

2013 ◽  
Vol 753-755 ◽  
pp. 1448-1452
Author(s):  
Song Hua Li ◽  
Ming Hao Feng ◽  
Xue Li ◽  
Yu Hou Wu ◽  
Xiao Lin Jin
Keyword(s):  
Machine Tool ◽  
High Speed ◽  
High Performance ◽  
Performance Test ◽  
High Hardness ◽  
Inertia Force ◽  
Rotational Inertia ◽  
Motorized Spindle ◽  
Advanced Ceramics ◽  
Low Thermal Expansion

One important demand on spindle systems in modern machine tools is to realize higher rotational speed in order to increase the machining efficiency. So, the low rotational inertia and high fundamental natural frequency are indispensable. Because of advanced ceramics' extraordinary physical properties such as high hardness, low thermal expansion, light weight, abrasion resistant and good chemical and thermal stability, it accommodates very well the high-speed and precision requirements of machine tool spindles. In this study, a high-speed ceramic spindle system equipped with high-performance structural ceramic shaft and fully-ceramic ball bearings was designed and developed. The high-speed ceramic motorized spindle prototype was assembled with high precision successfully, and its performance test and analysis were finished. The test results show that ceramic motorized spindle can reduce the high-speed rotational centrifugal force and inertia force and increase the stiffness and rotation accuracy of spindle-bearing system greatly.

CPM REX 25

Alloy Digest ◽  
1980 ◽  
Vol 29 (7) ◽  
Keyword(s):  
Heat Treatment ◽  
High Speed ◽  
High Speed Steel ◽  
High Hardness ◽  
Heat Treating ◽  
High Speeds ◽  
Aisi Type ◽  
Tool Performance ◽  
End Mills ◽  
Machining Operations

Abstract CPM REX 25 is a super high-speed steel made without cobalt. It is comparable to AISI Type T15 cobalt-containing high-speed steel in response to heat treatment, properties, and tool performance. CPM REX 25 is recommended for machining operations requiring heavy cuts, high speeds and feeds, and difficult-to-machine materials of high hardness and abrasion resistance. Typical applications are boring tools, drills, gear cutters, punches, form tools, end mills and broaches. This datasheet provides information on composition, physical properties, hardness, and elasticity as well as fracture toughness. It also includes information on forming, heat treating, machining, and surface treatment. Filing Code: TS-365. Producer or source: Crucible Materials Corporation.

TATMO V-N

Alloy Digest ◽  
1985 ◽  
Vol 34 (12) ◽  
Keyword(s):  
High Speed ◽  
Cutting Tool ◽  
High Speed Steel ◽  
High Hardness ◽  
Heat Treating ◽  
Nitrogen Addition ◽  
Aisi Type ◽  
End Mills ◽  
Red Hardness ◽  
Edge Toughness

Abstract TATMO V-N is an AISI Type M7 high-speed steel modified by alloy balancing and a nitrogen addition to develop superior hardness response in heat treatment. It is an excellent grade for many cutting-tool applications requiring an optimum balance of red hardness, edge toughness and wear resistance, such as drills, taps, end mills, reamers and milling cutters. Its combination of outstanding properties and high hardness makes Tatmo V-N a logical alternate for cobalt high-speed steels in many cutting-tool applications. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, machining, and surface treatment. Filing Code: TS-452. Producer or source: Latrobe Steel Company.

Research on High-Speed Cutting of Cr12MoV Hardened Steel - A Review

2020 ◽  
Vol 15 ◽  
Author(s):  
Fei Sun ◽  
Guohe Li ◽  
Qi Zhang ◽  
Meng Liu
Keyword(s):  
High Speed ◽  
Cutting Temperature ◽  
High Hardness ◽  
High Strength ◽  
Hardened Steel ◽  
Parameters Optimization ◽  
Future Research ◽  
High Speed Machining ◽  
Machined Surface ◽  
Stamping Die

: Cr12MoV hardened steel is widely used in the manufacturing of stamping die because of its high strength, high hardness, and good wear resistance. As a kind of mainstream cutting technology, high-speed machining has been applied in the machining of Cr12MoV hardened steel. Based on the review of a large number of literature, the development of high-speed machining of Cr12MoV hardened steel was summarized, including the research status of the saw-tooth chip, cutting force, cutting temperature, tool wear, machined surface quality, and parameters optimization. The problems that exist in the current research were discussed and the directions of future research were pointed out. It can promote the development of high-speed machining of Cr12MoV hardened steel.

scholarly journals Design and Fabrication of a High-Speed Atomic Force Microscope Scan-Head

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 362
Author(s):  
Luke Oduor Otieno ◽  
Bernard Ouma Alunda ◽  
Jaehyun Kim ◽  
Yong Joong Lee
Keyword(s):  
Atomic Force Microscope ◽  
Natural Frequency ◽  
High Speed ◽  
Contact Mode ◽  
Ongoing Process ◽  
Atomic Force ◽  
Constant Height ◽  
Mode Tracking

A high-speed atomic force microscope (HS-AFM) requires a specialized set of hardware and software and therefore improving video-rate HS-AFMs for general applications is an ongoing process. To improve the imaging rate of an AFM, all components have to be carefully redesigned since the slowest component determines the overall bandwidth of the instrument. In this work, we present a design of a compact HS-AFM scan-head featuring minimal loading on the Z-scanner. Using a custom-programmed controller and a high-speed lateral scanner, we demonstrate its working by obtaining topographic images of Blu-ray disk data tracks in contact- and tapping-modes. Images acquired using a contact-mode cantilever with a natural frequency of 60 kHz in constant deflection mode show good tracking of topography at 400 Hz. In constant height mode, tracking of topography is demonstrated at rates up to 1.9 kHz for the scan size of 1μm×1μm with 100×100 pixels.

Dissolution Behavior of Cast WC Particles in NiCrBSi-WC Coatings by Laser Induction Hybrid Cladding

2013 ◽  
Vol 668 ◽  
pp. 283-287
Author(s):  
Sheng Feng Zhou ◽  
Xiao Qin Dai
Keyword(s):  
High Speed ◽  
Laser Scanning ◽  
Metallic Matrix ◽  
High Hardness ◽  
Scanning Speed ◽  
Eutectic Structure ◽  
Dissolution Behavior ◽  
Positive Role ◽  
Laser Scanning Speed ◽  
Laser Induction

In order to characterize the dissolution of cast WC particles in Ni-based WC coatings by laser induction hybrid rapid cladding, NiCrBSi+50 wt.% WC coatings are produced on A3 steel by low and high speed laser induction hybrid cladding (LIHC). When laser scanning speed is only 600 mm/min, the crack-free coating has pores and its dilution is as high as 45%. At the bottom of coating, the cast WC particles are dissolved completely and the herringbone M6C eutectics are precipitated. In the center of coating, the cast WC particles are also dissolved completely and the acicular, blocky and dendritic carbides with relatively low hardness are precipitated. At two sides of coating, some cast WC particles are dissolved partially and interact with Ni-based alloy to form an alloyed reaction layer, while others preserve the primary eutectic structure and high hardness. When laser scanning speed and powder feeding rate are increased to 1500 mm/min and 85.6 g/min, the coating has cracks but no pores. Its dilution can be markedly decreased to 7.8%. Moreover, a majority of WC particles are still composed of primary eutectic structure and keep their high hardness, which can play a positive role in strengthening Ni-based metallic matrix.

scholarly journals Effect of Deep Cryogenic Treatment on Corrosion Properties of Various High-Speed Steels

Metals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 14
Author(s):  
Jure Voglar ◽  
Živa Novak ◽  
Patricia Jovičević-Klug ◽  
Bojan Podgornik ◽  
Tadeja Kosec
Keyword(s):  
High Speed ◽  
Cryogenic Treatment ◽  
Test Procedure ◽  
High Speed Steel ◽  
High Hardness ◽  
Polarization Measurement ◽  
Deep Cryogenic Treatment ◽  
Corrosion Properties ◽  
Potential Measurement ◽  
Corrosion Studies

The aim of the study was to evaluate the corrosion properties of three different grades of high-speed steel following a heat treatment procedure involving deep cryogenic treatment after quenching and to investigate how these properties are connected to the microstructure and hardness of the material. The hardness of steels was measured, and microstructural properties were determined through observation of the metallographically prepared steels using scanning electron microscopy. These studies were complemented corrosion evaluation by the use of corrosion potential measurement and linear polarization measurement of steels in a sodium tetraborate buffer at pH 10. The results showed that the deep cryogenic procedure of high-speed steel changed the microstructure and consequently affected the hardness of the investigated steels to different extents, depending on their chemical composition. Corrosion studies have confirmed that some high-speed steels have improved corrosion properties after deep cryogenic treatment. The most important improvement in corrosion resistance was observed for deep cryogenically treated high-speed steel EN 1.3395 (M3:2) by 31% when hardened to high hardness values and by 116% under lower hardness conditions. The test procedure for differentiating corrosion properties of differently heat-treated tool steels was established alongside the investigation.

Hardening of Selective Laser Melted M2 Steel

2021 ◽  
Author(s):  
Mei Yang ◽  
Yishu Zhang ◽  
Haoxing You ◽  
Richard Smith ◽  
Richard D. Sisson
Keyword(s):  
Heat Treatment ◽  
High Speed ◽  
Cutting Tools ◽  
High Speed Steel ◽  
High Hardness ◽  
Steel Part ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Near Net Shape

Abstract Selective laser melting (SLM) is an additive manufacturing technique that can be used to make the near-net-shape metal parts. M2 is a high-speed steel widely used in cutting tools, which is due to its high hardness of this steel. Conventionally, the hardening heat treatment process, including quenching and tempering, is conducted to achieve the high hardness for M2 wrought parts. It was debated if the hardening is needed for additively manufactured M2 parts. In the present work, the M2 steel part is fabricated by SLM. It is found that the hardness of as-fabricated M2 SLM parts is much lower than the hardened M2 wrought parts. The characterization was conducted including X-ray diffraction (XRD), optical microscopy, Scanning Electron Microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) to investigate the microstructure evolution of as-fabricated, quenched, and tempered M2 SLM part. The M2 wrought part was heat-treated simultaneously with the SLM part for comparison. It was found the hardness of M2 SLM part after heat treatment is increased and comparable to the wrought part. Both quenched and tempered M2 SLM and wrought parts have the same microstructure, while the size of the carbides in the wrought part is larger than that in the SLM part.

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