ICMCTF2016 Session GP: Symposium G Poster Session

Thursday, April 28, 2016 5:00 PM in Room Grand Hall

Thursday Afternoon

Time Period ThP Sessions | Topic G Sessions | Time Periods | Topics | ICMCTF2016 Schedule

GP-1 High Density Plasma Nitriding of Tantalum
Tatsuhiko Aizawa (Shibaura Institute of Technology, Japan); Shin-Ichi Matsumoto (San-Ei Precision, Co. Ltd., Japan)
Refractory metals have been utilized as a structural part to be working at the elevated temperature; e.g., tungsten and its alloys are utilized as a substrate for sputtering and an electric joining punch. Tantalum becomes also popular in usage as an electric wire and a mechanical part working at high temperature. Different from the tungsten, the tantalum has much ductility with lower hardness so that selective hardening should be essential to prolong the life time of tantalum parts and to assist the shaping and machining processes in practice. Both the nitriding and oxi-nitriding processes have been developed to fabricate the TaN and TaON, respectively. Very few studies were reported on the plasma nitriding of tantalum to yield the solid solution tantalum, Ta (N) and the tantalum nitride (TaN). In the present paper, the high density plasma nitriding with use of higher ion density than 5 x 1016 m-3 is utilized to make plasma nitriding of pure tantalum with the purity of 99.99 %. The plasma nitrided tantalum specimen at 693 K for 14.4 ks has much higher hardness than that before nitriding; e.g. its surface micro-Vickers hardness by 1 N reaches to 1300 HV in average. In addition, the nitrided layer thickness is 40 μm in depth. SEM-EDX, XRD and XPS are utilized not only to describe the nitrogen solute diffusion process during the present nitriding but also to investigate the effect of holding temperature on the formation of TaN and Ta(N).
GP-2 HPPMS (Cr1-xAlx)N+MoSy Coatings for Lubricant-Free Cold Forging of Steel
Kirsten Bobzin, Tobias Brögelmann, Nathan Kruppe, Serhan Basturk, Fritz Klocke, Patrick Mattfeld, Rafael Hild, Daniel Trauth (RWTH Aachen University, Germany)

Cold forging is a manufacturing process which is of great importance due to the maximum degree of material utilization, the associated energy and the resource efficiency in production technology. Commonly, lubricants are applied to reduce friction between workpieces and forming tools in cold forging processes. Due to significant advances in solid lubricant coatings deposited by physical vapor deposition (PVD) in the recent years, coatings took over the tasks of lubricants in numerous applications. However, most attempts to realize dry metal cold forging of steel failed so far. High power pulsed magnetron sputtering (HPPMS) (Cr1‑xAlx)N+MoSy coatings are promising candidates in order to replace lubricants on highly loaded tools in dry cold forging. Wear resistant (Cr1‑xAlx)N extended by the self-lubricating MoSy offers an extension of tool life without lubricants. HPPMS technology offers outstanding advantages in terms of high hardness and dense morphology. In addition to that, complex-shaped forging tools with surfaces oriented non-parallel to the target can be coated by using HPPMS. In the present work (Cr1-xAlx)N+MoSy coatings were deposited on X155CrMoV12 tool steel by means of HPPMS using an industrial scale PVD unit. An especially designed target consisting of a CrAl half and a MoS2 half in form of triangles was used, which leads to a variation of the chemical composition of the deposited coatings dependent on the substrate position within the coating chamber. Coating thickness and morphology were determined by using Scanning Electron Microscopy (SEM). Transmission electron microscopy (TEM) was used to determine crystal structure. For this purpose, the coating was prepared by means of focused ion beam (FIB). Glow Discharge Optical Emission Spectroscopy (GDOES) was used to analyze the composition. The surface roughness was measured by means of confocal laserscanning microscopy (CLSM). Phase composition was investigated by using X-Ray Diffraction (XRD). Universal hardness HU and indentation modulus EIT were measured by using nanoindentation. A pin-on-disc tribometer (PoD) was used to simulate the tribological behavior during dry contacts. Decreasing the Mo and S contents by increasing Cr and Al contents leads to considerable influences on the coating properties. It was found that universal hardness and indentation modulus increase with decreasing Mo and S contents. A reduction of the friction coefficient with the addition of Mo and S was observed. The coating (Cr1-xAlx)N together with the self-lubricating MoSy deposited using HPPMS technology has a high potential for lubricant-free cold forging of steel.

GP-4 In Situ Nanoindentation of Hard Coatings at Elevated Temperatures
Marcus Hans (RWTH Aachen University, Germany); Ude Hangen, Chen Peng (Hysitron, Inc., Germany); Esmail Asadi, Marc Wurz (Leibniz University Hannover, Germany); Jochen Schneider (RWTH Aachen University, Germany)

Commonly, temperature-induced modifications in the mechanical properties of hard and protective coatings are determined by nanoindentation after heat treatment. We report elastic modulus and hardness values of (Ti0.55Al0.45)0.49N0.51 at temperatures of up to 600°C, measured by in situ nanoindentation with a Hysitron TI-950 TriboIndenter, equipped with a xSol™ high temperature heating stage. The coatings were deposited onto single crystalline Si (100) and Al2O3 (0001) by reactive cathodic arc deposition in an industrial deposition system at 450°C. Prior to nanoindentation tests, the coatings were prepared by chemical mechanical polishing to reduce the surface roughness. Continuous stiffness and hardness measurements were employed to determine the mechanical properties as a function of contact depth. The differences between in situ and ex situ data clearly underline the significance of in situ testing for the investigation of hard and protective coatings.

GP-5 Evaluation of PVD Hard Coating Deposited on Aluminum Casting Die
Mauricio Avelino (Faculdade de Tecnologia SENAI Joinville, Brazil); Gabriel Chiquetti, Alexsandro Rabelo, Ivonete Ostrovski (Instituto Senai de Inovação em Sistemas de Manufatura, Brazil); José Paiva Junior (Instituto Senai de Inovação em Laser, Brazil); Wilmar Mattes (Centro Universitário Católica de Santa Catarina, Brazil)

This paper presents a study of hard coatings obtained by physical vapor deposition PVD applied to components of a mold used for the injection of aluminum. During the experimental development, it was required find out a solution through PVD coating to contribute to the reduction of friction in the mold components and consequently improve the extraction of parts, seen as a negative impact of problem during the casting process. The purpose of this study was to assess PVD coatings, testing three different coatings rich in Aluminum and Chromium. Through these coatings was analyzed its structure and evaluated their performance when subjected to testing in normal production conditions.

GP-7 Tribological Analysis of Laser Structured Oxynitride Hard Coatings Deposited by Middle Frequency Magnetron Sputtering for Application in Plastics Processing
Kirsten Bobzin, Tobias Brögelmann, Nathan Kruppe, Mona Naderi, Christian Kalscheuer (Surface Engineering Institute - RWTH Aachen University, Germany)

One of the fast-growing segments of manufacturing is plastics processing. The properties of plastic products can be optimized by a suitable design of the component surface. One promising method is the usage of molding tools structured in the micrometer range for plastics processing by extrusion and injection molding. Such microstructured, optically functional plastic parts are commonly used in light-field photography, displays and security technology. However, the adhesion of the plastic melt on the mold surface during the processing can shorten the life time of mold inserts under possible abrasive wear and corrosion. Physical vapor deposition (PVD) is a technology for deposition of hard wear resistant coatings on a variety of technical tools and components. PVD hard coatings, such as ternary and quaternary chromium based nitride (Cr1-xAlx)N and oxynitride (Cr1-xAlx)ON, are used as protective coatings due to their mechanical, chemical and tribological properties to reduce wear, corrosion and adhesion forces between mold insert and plastic.

Within the scope of this paper, oxynitride hard coatings deposited by means of middle frequency pulsed magnetron sputtering (mfMS) on steel substrates AISI 420 were investigated. The oxygen flows F(O2) = 10 sccm, 15 sccm and 20 sccm were selected due to their high universal hardness HU and indentation modulus EIT of the coatings. A laser microstructuring was carried out by Institute For Laser Technology with a depth of s = 1,5 µm on the coatings was subsequently performed. The influence of the oxygen content on the coatings morphology and its chemical composition as well as on the mechanical and tribological properties was characterized. With increasing oxygen flow, universal hardness and indentation modulus increased from HU = 8.6 ± 3.1 GPa and EIT = 189.73 ± 52.9 GPa to HU = 16.8 ± 3.0 GPa to EIT = 252.27 ± 38.4 GPa. Makrolon® LED2245 was considered for tribological investigations. Adhesion behavior of molten polycarbonate on (Cr1-xAlx)ON hard coatings was analyzed by high temperature contact angle measurements. Wear tests were performed by using pin-on-disc-tribometer measurements at room temperature T = 23 °C and higher tempreture T =150 °C against solid Polycarbonate. The coatings were structured successfully by laser and a prosperous deforming could be proofed. The mfMS Cr0,39Al0,05O0,21N0,35 hard coatings deposited by using an oxygen flow rate of F(O2) = 20 sccm showed the lowest wear rates due to their higher hardness. The results indicate a high potential of the investigated oxynitride coatings to be used as protective coatings against abrasive and adhesive wear during processing of polycarbonate.

GP-8 Development of (Cr,Al)N/(Cr, Al)ON Oxynitride Multilayer Coatings Deposited by Hybrid dcMS/HPPMS for Plastics Processing Applications
Kirsten Bobzin, Tobias Brögelmann (Surface Engineering Institute - RWTH Aachen University, Germany); Guido Grundmeier, Teresa de los Arcos, Martin Wiesing (University of Paderborn, Germany); Ricardo Brugnara, Nathan Kruppe, Mostafa Arghavani (Surface Engineering Institute - RWTH Aachen University, Germany)
In plastics industry injection molding and extrusion tools are subjected to adhesive and abrasive wear by the flowing hot melt during extrusion process and adhering solidified melt. Due to their beneficial properties, chromium-based nitride hard coatings deposited by physical vapor deposition (PVD) are applied as protective coatings. As the chemical composition of a coating determines primarily the chemical composition of the reaction layer that is forming at the surface by the air, chromium-based oxynitride coatings with increased oxygen contents have a high potential to be used on plastic processing tools. The PVD hybrid technology, consisting of direct current and high power pulse magnetron sputtering dcMS/HPPMS, combines the advantages of both technologies, such as a high deposition rate of dcMS and a smooth coating with dense morphology and a higher universal hardness of HPPMS. In the presented work, different synthesized oxynitride multilayer coatings (Cr,Al)N/(Cr,Al)ON deposited on tool steel substrate AISI 420 (X42Cr13, 1.2083) by hybrid dcMS/HPPMS technology were investigated. In the deposition process of the oxynitride (Cr,Al)ON toplayers, the oxygen flux was varied in the range between F(O2) = 0 sccm and F(O2) = 50 sccm. All coatings were investigated with regard to the coating properties, the compound properties to and substrate and the long-term behavior against Makrolon® 2408 polycarbonate (PC2408). By means of energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) the influence of the varied oxygen flux on the chemical composition of the coating and the reaction formed was investigated. It was shown, that an increasing oxygen flux in the deposition process from F(O2) = 0 sccm to F(O2) = 50 sccm leads to a decreasing nitrogen content from 35 at.-% to 21 at.-% and an increasing oxygen content from 2.5 at.-% to 11 at.-% in the oxynitride toplayer and a significant increase of the oxygen content in the reaction layer from 24 at.-% to 37 at.-% influencing morphology, mechanical properties and topography. Adhesion behavior between the coatings towards molten polycarbonate PC2408 by high temperature contact angle measurements and analyses of the bonding strength between the coatings and solidified PC2408 by pull-off tests according to DIN EN ISO 4624:2014-06 revealed a significant influence of the coatings’ chemical composition. These tests verified a positve influence of an increased oxygen content in the toplayer on the adhesion behavior towards polycarbonate PC2408. This makes oxynitride multilayer coatings (Cr,Al)N/(Cr,Al)ON a promising candidate for injection molding or extrusion tools.
GP-9 Strained Ge Metal Insulator Semiconductor Field Effect Transistor with Ge Thin Film
Min-Hung Lee (National Taiwan Normal University, Taiwan, Republic of China); Shu-Tong Chang (Natioanl Chung Hsing University, Taiwan, Republic of China); Sally Liu (National Taiwan Normal University, Taiwan, Republic of China)

Strained Ge channel N type metal-insulator-semiconductor transistor including the biaxial compressive strain thin Ge film grown on Si substrate by ultra high vacuum chemical vapor deposition is demonstrated, and the performance enhancement experimentally is also exhibited. The drive current and subthreshold swing of strained Ge transistor is better than Si control device. The on-off current ratio is reaching the eight order without sacrificing the leakage current. For the mobility enhancement, Ge device exhibits over 100% enhancement compared with the Si one. To develop strained Ge N type and P type metal-insulator-semiconductor transistor with Ge thin film for CMOS technology without III-V material may have nanoscale feasibility be the future generation and compatible to present CMOS process.

GP-10 Influence of Interlayer Design on the Mechanical Properties of AlTiN/TiBN Multilayered Coatings Synthesized by Cathodic Arc Evaporation
Yin-Yu Chang, Yu-Chin Chen, Jun-Hao Zhou (National Formosa University, Taiwan, Republic of China); Chi-Lung Chang (MingDao University, Taiwan, Republic of China)
Transition metal nitrides, such as AlTiN, TiN and TiBN, have been used as protective hard coatings due to their excellent tribological properties. In this study, AlTiN/TiBN coatings were synthesized by cathodic-arc evaporation. AlTi and TiBalloy cathodes were used for the deposition of gradient and multilayered AlTiN/TiBN coatings. During the coating process of AlTiN/TiBN, different interlayers of AlTiN and TiBN were deposited to enhance mechanical properties and adhesion strength between the coatings and substrates. The multilayer thickness and alloy content of the deposited coating were correlated with the evaporation rate of cathode materials. By controlling the cathode current and rotation speed, the deposited multilayered AlTiN/TiBN coatings possessed periodic AlTiN and TiBN layers. The microstructure of the deposited coatings was investigated by a field emission gun high resolution transmission electron microscope (FEG-HRTEM), equipped with an energy-dispersive x-ray analysis spectrometer (EDS). Glancing angle X-ray diffraction was used to characterize the phase identification and residual stresses of the films. The composition was evaluated by auger electron spectroscopy (AES) . Mechanical properties, such as the hardness and elastic modulus, were measured by means of nanoindention. To evaluate the correlation between impact fracture resistance and hardness/elastic modulus ratio of the deposited coatings, an impact test was performed using a cyclic loading device with a tungsten carbide indenter as an impact probe. The design of gradient and multilayered AlTiN/TiBN coatings by using proper interlayers is anticipated to increase the adhesion, hardness, toughness and tribological resistance of coatings.
GP-11 Dedicated PVD Coating Development for High-Performance Gear Hobbing
Andreas Lümkemann (PLATIT AG, Advanced Coating Systems, Switzerland); Martin Beutner (Otto von Guericke University, Germany); Marcus Morstein, Tibor Cselle (PLATIT AG, Advanced Coating Systems, Switzerland); Bernd Karpuschewski (Otto von Guericke University, Germany)

Gear hobbing is the most common cutting process for green manufacturing of gears. The cutting conditions regarding chip thickness and cutting length change continuously within every generating position. Hence, the load at the cutting edge varies critically too and affects abrasive and crater wear on the tool. Nowadays gear hobbing is performed more and more without coolant which intensifies the wear phenomena.

To examine the performance of different coatings, cutting trials were carried out using the well-established fly-cutter analogy test. Subsequently the worn out single hob teeth are examined by REM and fringe projection to evaluate the wear phenomena.

To reduce crater wear and to extend the lifetime of gear cutting tools a range of AlCrN-based coatings was deposited in an industrial π411 rotating arc cathodes PVD unit. Significant performance differences between the chemically and structurally modified coatings were found. Doping the coating top layer with titanium in combination with an optimized nanolayer structure lead to a substantial increase of tool life.

GP-12 The Study of Electrical Conductivity and Mechanical Strength on BipolarPlate via Different Surface Sputtering
Ai-Huei Chiou (National Formosa University, Taiwan, Republic of China); Shinn-Dar Wu (MingDao University, Taiwan, Republic of China)
The bipolar plate has occupied 90% volumes in the fuel cell stacks and affects the fuel cell’s conductivity and manufacturing cost. The traditional bipolar plate materials include metal ' graphite and carbon composite material have several problems. This research used PMMA as the foundation plate and different types of metallic film were deposited by sputtering.

Non-conductor metallization technique was used prepare the bipolar plate. The physical properties of the PMMA board surface could be changed by the machinery roughen treatment, then the board was coated via sputtering method with different metallic film (Ti ' Cr ' Zr ' Cu),and finally discusses influence in the PMMA surface the adhesion ' electrical properties ' physical and chemical properties of the PMMA with the different metallic films were tested and discussed.

From the results of performance test, it was shown that the Cu film is better than others. This study results also showed that this pre-coated copper film can provide good conductivity and future process of electroplating.

Time Period ThP Sessions | Topic G Sessions | Time Periods | Topics | ICMCTF2016 Schedule