running projects

Improved HPPMS process control through a downstream positive bias pulse

Project-No. F23226N | EFDS-No. IGF-21-10

project period: 01.07.2024 – 30.06.2026

research institution

RWTH Aachen, Institut für Oberflächentechnik

abstract

Physical vapor deposition (PVD) is used with a steadily growing market share for wear protection on components and tools in order to increase service life and performance. Residual stresses are of particular importance here. In industrial sputtering processes, such as High Power Pulsed Magnetron Sputtering (HPPMS), process gases such as argon are used to extract atoms or ions of the layer-forming material from a target material. In addition to the target, the argon ions, some of which are highly energetic, also strike the growing coating through the applied bias voltage. This results in the implantation of these ions into the coating and thus an influence on the residual stresses. This can affect the mechanical properties and therefore the cutting performance of the tools. During the pulse time of an HPPMS process, the concentration of argon ions in the coating plasma changes. In the proposed research project, a positive bias pulse is synchronized with the HPPMS cathode pulse in such a way that the argon implantation and thus the residual stress state can be controlled. In order to analyze the influence of the positive bias pulse on the plasma properties such as the composition of the coating plasma and the ion energy, plasma diagnostics such as optical emission spectroscopy, mass spectrometry and counter-field analysis are used. The results of the plasma analyses are correlated with the layer properties of the coating, such as the residual stresses and the chemical composition. The research project will extend conventional HPPMS process control in order to increase the cutting performance of tools by adjusting the residual stress state. SMEs in the field of industrial power supplies, PVD system manufacturers, manufacturers of plasma diagnostics and cutting tools will therefore benefit from the results.

Plasma surface modification to improve the performance and cost efficiency of fuel cell components

Project-No. F23260N | EFDS-Nr. IGF-22-03

project period: 01.03.2024 – 31.08.2026

research institution

Technische Universität Darmstadt
Technische Universität Braunschweig

Abstract

The use of austenitic rust and acid-resistant (RS) steels for bipolar plates in fuel cells and hydrogen electrolysis offers enormous potential for cost and volume savings as well as for increasing efficiency compared to graphite-based bipolar plates and at the same time represents an economical alternative to other titanium or nickel-based materials. However, the natural passive layer of RS steels requires additional surface treatment. Surface modification using plasma diffusion processes would represent an alternative to PVD / CVD-based processes, particularly in terms of coating costs, material consumption and energy balance, and would increase sustainability. The aim of the proposed project is to develop plasma diffusion processes to improve the performance and cost efficiency of fuel cell components.

The intended results hold the following innovation potential:

– Scientific and technical basis for the production of robust and inexpensive bipolar plates
– Identification of process parameter-property interactions
– Economic advantages through optimization of material selection, treatment parameters and production costs
– Consideration of the flow-dynamic, thermal and electrical stress collective under
practical conditions and research into degradation mechanisms
– Ecological advantages through ensuring or increasing the component service life

Thus, the benefits and significance of the project are very high, especially for SMEs. The potential user group of the research project concerns the following economic sectors (according to the IGF guidelines): 24 (metal production and processing); 28 (mechanical engineering), 35 (energy generation), 29 (manufacture of motor vehicles and motor vehicle parts) and 30 (other vehicle construction).

Development of production process sequences for coated metallic bipolar plates for fuel cells of the highest quality and energy efficiency

Project-No. 22948 BG | EFDS Nr. IGF-20/11

project period: 01.07.2023 – 30.06.2025

research institution

Fraunhofer-Institut für Werkzeugmaschinen und Umformtechnik IWU, Chenitz
Fraunhofer-Institut für Schicht- und Oberflächentechnik IST, Braunschweig
Fraunhofer-Institut für Werkstoff- und Strahltechnik IWS, Dresden

Abstract

PEM fuel cells offer enormous potential for reducing greenhouse gas emissions. However, their current use is limited by uneconomical large-scale production. The aim of this project is to develop and test new production routes for metallic BPPs. This includes the combination of two different coating approaches and forming processes:
Solution approach 1: Here, functional carbon layer systems are produced that are intended to retain their high electrical conductivity and corrosion resistance even after forming. A comparison between ARC evaporation and magnetron sputtering is carried out here. HIPIMS is also taken into account.
Solution approach 2: In this new production method for BPP, contrary to the current state of the art, a metallically pre-coated plate is functionalized after forming by a plasma diffusion treatment in order to minimize defects as a result of forming and to avoid corrosion initiation sites.
Solution approaches for forming: Three different processes are to be used for forming (hollow embossing, embossing rolls, hydroforming). Integration of solution approaches from the PA: The participating PA and in particular the participating SMEs are given the opportunity to apply their own coatings and have them analyzed or evaluated in order to compare their own state of the art with that of research and to secure a technological advantage. The direct benefit of the research results for SMEs arises above all from the increased know-how regarding the properties and limits of the coating and forming processes investigated and their effect on the operating conditions of the BPP, which is developed together with participating large companies and scientific institutions. This knowledge gives the companies involved a competitive edge.

Resource-efficient plasma nitriding of stainless steels for combined tribological and corrosive stresses

AiF-Nr. 22449 N | EFDS-Nr. IGF-19/14

project period: 01.08.2022 – 31.01.2025

research institution

Technische Universität Darmstadt, Staatliche Materialprüfungsanstalt Darmstadt
Technische Universität Braunschweig, Institut für Oberflächentechnik

Abstract

Austenitic steels are often plasma nitrided, particularly in the food industry, medical technology and chemical plant engineering, to increase wear protection. Wear resistance is dominated by the thickness of the hard S phase formed during plasma nitriding. The steel used and the material structure significantly influence the thickness of the S-phase and the corrosion behavior under otherwise identical treatment conditions. Therefore, maintaining the corrosion resistance of plasma nitrided steels is still problematic and cannot be guaranteed in a reproducible manner.
The aim is to determine parameters for a plasma nitriding treatment that is individually optimized for the material and material condition of austenitic steels in order to achieve the target values to be achieved in terms of wear protection in a process-safe manner and at the same time maintain the corrosion resistance.
The desired results have the following innovation potential:

– Scientific and technical basis for the selection of treatment parameters during plasma nitriding
– Identification of limit values and parameter windows to ensure reproducible treatment results
– Economic advantages due to the material-adapted optimization of the treatment parameters as well as the reduction of damage or complaints
– Ecological advantages by ensuring or increasing the service life of components
– Gain in confidence through improved advice and product quality for reproducible achievement of the required corrosion and wear protection

Thus, the benefits and significance of the project are very high, especially for SMEs. The potential user group concerns the economic sectors 24 (metal production and processing); 28 (mechanical engineering), 29 (manufacture of motor vehicles and motor vehicle parts), 30 (other vehicle construction) as well as 20 (manufacture of chemical products) and 21 (manufacture of pharmaceutical products).

Corrosion optimization of ternary PVD hard nitride coatings.

AiF-Nr.22641 N | EFDS-Nr. IGF-20/10

project period: 01.10.2022 – 31.03.2025

research institution

Darmstadt University of Technology, State Materials Testing Institute Darmstadt

abstract

The aim of the proposed project is to extend the property profiles of functionally optimized ternary PVD hard nitride coatings to include the function of effective corrosion protection. The concept of alloying Mg-Gd to TiN developed by the applicant research institution and the knowledge gained about the influencing factors for ensuring wear and corrosion protection are to be transferred in this project to typical ternary coating systems (e.g. TiAlN, CrAlN, TiCN) in order to strengthen these coatings for use under corrosive conditions.
The results aimed for in the project have the following benefits for SMEs:
1. Development of new industrial application fields for corrosion-optimized PVD coatings under simultaneous corrosive and tribological stress.
2. improvement of environmental and health protection through the possibility of substituting corrosion-optimized ternary PVD hard nitride coatings for the electroplated coatings or electroless nickel previously used in corrosive environments.
3. Economic advantages, since corrosion-optimized ternary PVD hard nitride coatings can achieve greater added value compared to conventional PVD coating systems at similar coating costs due to the improved properties.
4. Increased sustainability, optimal utilization of shifts and reduced maintenance costs through
“predictive maintenance” concepts.
Manufacturers of coating systems, coating companies and users from practically all manufacturing sectors are often classified as SMEs. With the desired project results, new business areas and applications can be opened up through the use of corrosion-optimized ternary PVD hard nitride coatings by removing existing obstacles or safety concerns when using PVD coatings for components subject to corrosive stress.

Evaluation of fatigue behavior on PVD coatings by means of vibration-induced cavitation - Kaverm

AiF-Nr. 21807 N | EFDS-Nr. IGF-17/10

project period: 01.05.2021 – 31.10.2023

Research institutions:
Technical University of Darmstadt, State Materials Testing Institute Darmstadt

Abstract:
Within the planned research project, fatigue stress is to be investigated with regard to the adhesion properties of functional coatings across the entire surface. For this purpose, application-relevant PVD coating systems (DLC, t aC, a C:H:Me) are to be selected in consultation with industry and samples or component sections are to be coated or made available. The necessary fatigue loading is to be generated by acoustic cavitation using ultrasonic coupled transducers (sonotrodes). The ASTM International (American Society for Testing and Materials) standard ASTM G32-16 provides a general test specification for tests on the ultrasonic coupling transducer, which is to be modified and further developed in the project. The test parameters (frequency, amplitude, test duration, medium, etc.) are varied with the aid of high-speed camera recordings in order to be able to evaluate the resulting stress in relation to the input variables in a spatially resolved manner. Based on the results, a comprehensive evaluation of the two-dimensional adhesion properties of the coatings relevant to the application as well as the suitability of the ultrasonic coupling oscillator method should be possible. The targeted parameter variations and the evaluation of the resulting interactions due to the changed stress combination form the basis of the qualifying further development of the cavitation investigation. The influence of the microstructure (e.g. columnar, amorphous structures, multilayer layers), as well as the possible developing crack growth within the coating are in the focus of the mechanistic description. The sonotrodes of the
ultrasonic coupling transducer are also to be adapted to specifically influence the cavitation in order to allow testing on simply contoured and curved functional surfaces for possible prenormative research.

Development of tribologically optimized tool surfaces for economical forming of high-strength Ti(Al) alloys at 750-1250°C

AiF-Nr. 22645 BG | EFDS-Nr. IGF-18/04

project period: 01.10.2022 – 30.09.2024

Research centers
Fraunhofer-Institut für Werkzeugmaschinen und Umformtechnik IWU, Chemnitz
Fraunhofer-Institut für Schicht und Oberflächentechnik IST, Braunschweig

Abstract

Very high temperatures of 750 up to 1250 °C are required for forming high-strength Ti(Al) alloys, which severely limits the choice of suitable tool materials. An additional limitation occurs due to the adhesion tendency of titanium and titanium aluminides, which cause problems during forming. The “bonding” can cause damage to the components and the tool. In addition, material wear is promoted by the tendency to adhesion. Adhesions or residues from the previous forming process act as abrasive particles during the subsequent forming process, causing the components and tools to wear as a result of the high forces. The focus of this research proposal is the development of tool coatings for the isothermal forming of Ti(Al) alloys. Suitable tribological investigations and forming model tests are used to investigate, evaluate, further develop and optimize the tribological behavior of the surface layer after plasma boron and diffusion alloying of high-temperature molybdenum-based materials such as titanium-zirconium-molybdenum, molybdenum-hafnium-carbon or zirconium-hafnium-molybdenum compared with Ti(Al) alloys. The manufacturers of Ti(Al) alloys, manufacturers of special materials for tools, toolmakers specializing in the processing of special materials and manufacturers of special lubricants are closely associated with this topic. Tool coatings and diffusion treatments for high-temperature forming are absolutely new territory for coating companies and contract treaters. Since the expected results can be transferred to the wear protection of other machine elements and tools subject to high thermal loads, there is also great interest from this side. Overall, the aim is to serve a highly specialized market for high-end products with a high SME share and very good growth prospects.

Self-lubricating TiBN coatings using pulsed arc PVD technology to reduce friction and wear

Project-No. 01|F23381N | EFDS-Nr. IGF-22-05

Duration: 01.09.2024 – 31.08.2026

Research institution

RWTH Aachen, Institut für Oberflächentechnik

Abstract

According to the current state of research and development, there are no self-lubricating PVD coatings for applications at T ≥ 500 °C that are based on a solid lubricant with a layered lattice structure. However, such a coating could lead to an increase in performance in applications such as machining and hot forming.
TiBN coatings with the solid lubricant hexagonal boron nitride (h-BN), which is oxidation-resistant up to T = 900 °C, are promising. TiBN coatings are already used in machining and hot forming. However, the TiBN coatings available on the market have so far only been produced using chemical vapor deposition at process temperatures of 900 °C ≤ T ≤ 1,100 °C. In hot forming tools, these high temperatures lead to component distortion and costly rework. The use of physical vapor deposition (PVD) has great potential. The technology variant of pulsed arc PVD is promising.
The research objective is to produce self-lubricating TiBN coatings with h-BN content using pulsed arc PVD technology to reduce friction in tribological applications in the high temperature range of 500 °C ≤ T ≤ 800 °C. The desired results are the identification of suitable process windows and layer architectures for producing the TiBN coatings. It is also being investigated how much the self-lubricating TiBN coatings increase in performance with regard to their tribological use in machining and hot forming. The expected results show a very high innovation potential. In addition, there is an extremely broad user base across several economic sectors, which are predominantly dominated by SMEs. This includes thin-film technology with its contract coaters, mechanical and plant engineering and their suppliers, target manufacturers and, last but not least, users in machining and hot forming.