Inovations of QSIL

At the request of a longstanding customer, QSIL Ceramics has further developed its metallization skills and now offers a metal / ceramic solution for applications that require reduced permittivity. Using this solution means high-strength, vacuum-tight metal-ceramic solder connections can be made between melting alloys (e.g. 1.3981 FeNi29Co18) and steatite ceramic. 

The advantage of Steatite 

• Steatite ceramic has lower permittivity units (relative dielectric constant) than Al2O3 ceramic. 
• The thermal conductivity of the steatite ceramic is approximately 10 times less than Al2O3 ceramic. 

Possible fields of application 
In the microwave range (GHz) in particular, the lower permittivity of the steatite ceramic leads to a higher transparency and thus to a lower weakening of the electrical field. A higher signal sensitivity can be achieved in sensor applications. This advantage was demonstrated on a specific component at the customer. He-leak testing also showed that the soldered joint withstood the demanding test conditions of 640 bar and thermal shocks from -196 ° C to 10 ° C or 470 ° C to 10 ° C. 

In addition to the vacuum-tight brazed ceramic-to-metal joinings offered as a standard solution, QSIL Ceramics offers its customers ceramic-metal feedthroughs produced by co-sintering platinum or platinum alloy pins into zirconia containing ceramic. Using the approach, high-strength, form-stable and vacuum-tight ceramic-metal joinings can be produced. 

What are the advantages? 
•  High chemical and hydrothermal stability 
•  Appropriate for contact with food in accordance with the regulation (EG) 1935/2004 and FDA 
•  Conformity regarding bioreactivity test in vitro / cytotoxicity according to USP <87> 
•  Tested application temperature 500 °C 
•  Platinum has very good electrical conductivity 

Possible fields of application 
•  Sensor technology 
•  Medical technology 
•  Electrical engineering 

 
The objective of the research project "High Performance Processes for High Performance Materials - HOch²" was the machine-side and technological improvement of electrical discharge machining technology for machining Si3N4- and SiC-based high-performance ceramics. The aim was to meet industrial demands for higher productivity while maintaining or increasing machining accuracy. Research approaches included parameter optimization and fundamental considerations of the ceramic-specific ablation mechanisms - also with the aim of enabling spark-erosive machinability even at low electrical conductivity. 
At the same time, the project involved further development of the ceramics in terms of conductivity/semiconductor properties while retaining their high-quality physical properties. Application-specific requirements were also considered. Furthermore, demonstrators were manufactured to show the spark-erosive machining accuracy of these materials on industrial examples. 
 

Ceramic membranes for water filtration are characterized by high chemical, thermal and mechanical stability and are therefore superior to polymer membranes in terms of performance and durability. An important issue in the field of wastewater treatment and water purification is the high risk of abrasion and module blocking. Simultaneously, there’s a problem with the high flow of contaminated water, which should be cleaned at a reasonable price. This challenge has to be solved by filter plates, which offer a high porosity and surface area to increase the (mass-specific) filtering performance. The completed project therefore used honeycomb ceramic membranes made of Silicon Carbide (SiC) and hollow fiber bundles with hydrophobic macropores for membrane distillation. Hydrophilic nanopores for nanofiltration were also developed together with the project partners. The scientific and technical work objectives were focused on thin-walled ceramic membranes with high pressure stability, adapted wettability and high volume-specific membrane areas. 

Si3N4 ceramics prove to be particularly suitable as rolling elements for bearing applications and as rolls and rollers for the hot forming of metallic semi-finished products due to their high abrasion resistance, crack resistance, high temperature strength and chemical resistance. Nevertheless, problems with regard to the reliability and service life of the rolling bearing or hot-rolled components are still apparent at particularly high mechanical and tribological loads or forming temperatures.

The research project "RoLiCer" therefore aims to optimize Si3N4 ceramics for rolling and rolling bearing processes with particular regard to the application-specific stresses and to develop models and calculation methods with which concrete predictions of reliability and service life in the application are possible. Furthermore, fundamental knowledge on material failure and crack propagation as a function of material structure and operating conditions, on adhesion and the processes in the contact zone between ceramics and metal, as well as on the design of components suitable for ceramics, is to be gained by means of simulation work, the investigation of material samples and load-bearing tests under application conditions.

The research work described is funded under Grant Agreement No. 263476 under the Seventh Framework Program of the European Union FP7/2007-2013.

In the project, a ceramic material and design solution was developed to substitute the previous graphite support crucibles in the hot zone of mc-Si crystal growth, with which a significant reduction of the impurity input into the Si melt can be achieved. This makes it possible to produce higher quality Si wafers for photovoltaics than before. Based on the application-specific requirements, suitable ceramic materials were first selected and further developed. In a next step, a modular crucible design concept was developed, which allows the technology to be scaled up step by step to pilot plant test sizes G1 and G2, and then upscaled to industrial production sizes. The positive results of the preliminary material tests were confirmed on the basis of prototypes of size G1.

As part of a project funded by the BMBF, two ZTA mixed oxide ceramics were developed based on raw materials with a grain size 
in the submicron range. The new materials are characterized by significantly improved mechanical properties compared to the 
existing standard ZTA material AZ. 

What are the benefits? 

• A minimum of 3 times higher wear resistance 
• > 20% higher bending strength compared to the standard ZTA-material AZ 90 
• > 10% higher fracture toughness 
• High surface quality, already Ra values after fine-tuning ≤ 0,1 µm (Rz ≤ 1,0 µm) 

Possible fields of application 
For applications in which high mechanical and wear resistance, high hardness and rigidity is required, the use of the AZ 90 F is recommended (e.g. mill components, linings, wear protection during water jet cutting, plain bearings). If the focus is on very high mechanical strength, good toughness and excellent surface quality, the use of the AZ 75 F is recommended as an inexpensive alternative to pure ZrO2 materials (e.g. knives, stirring disks, valve seats and balls).  

Beginning March 21st, new legal requirements for plastic and other organic materials in contact with drinking water will come into 
effect in Germany. Businesses and other providers of water supply systems must ensure that only organic materials are used for 
new and maintained drinking water extraction, treatment, or distribution systems. 
This is where built-in plastics and other organic materials in plants often reach their limits and ceramic materials can be the future-
proof solution.  
As a manufacturer of drinking water systems are you affected by this regulation? Then contact us. We are ready and able to help 
regularize your systems. 

Advantages of Ceramics 

• Chemical resistance: Aluminium oxide ceramic is an inert material that is resistant to many substances even at high temperatures. 
• Wear resistance: The high hardness of the materials at HV10 ≥15,000 N / mm² offers high resistance both in sliding wear and in impact wear. 
• Strength: The mechanical strength of our oxide ceramic materials exceeds that of porcelain or sanitary ceramics 
  many times over. 

Concentrated solar power (CSP), also known as solar thermal electricity (STE), is a promising technology because it directly harnesses the abundant solar energy striking the earth. According to rough estimates, a total of 85 petawatts of solar energy is available for terrestrial solar collectors, which is over 5000 times the current global electricity demand of around 15 terawatts. 
The main objective of this project was to significantly reduce the cost of concentrated solar power and to pave the way for its deserved competitiveness in the electricity market. In particular, the efficiency of the plant in converting solar energy into electrical energy was improved. FCT's contribution consisted of the design and manufacture of a ceramic receiver unit that enables higher operating temperatures. Ceramic components for the high temperature heat exchanger system were also supplied.

Trägersubstrate aus einkristallinem Aluminiumnitrid (AlN) sind ideal für die Abscheidung von halbleitenden (AlGaIn)N-Schichten, die u.a. als Basis für leistungsfähige und langlebige UV-Leucht- und Laserdioden gebraucht werden. Die großen Vorteile dieser Bauelemente kommen bislang jedoch nicht zum Tragen, da einkristalline AlN-Wafer nur sehr aufwändig und teuer an Forschungsinstituten für deren Eigenbedarf produziert werden können. Der wesentliche Grund hierfür ist das Fehlen geeigneter hochtemperatur- und korrosionsstabiler Tiegelmaterialien, welche sowohl den hohen Anforderungen des AlN-Einkristall-Züchtungsverfahrens als auch den wirtschaftlichen Vorgaben genügen.

Im geplanten Projekt befassen sich deshalb die FCT Ingenieurkeramik GmbH (FCT) zusammen mit dem Leibniz-Institut für Kristallzüchtung (IKZ) in Berlin mit der Entwicklung von refraktären keramischen Werkstoffen und Kompositwerkstoffen sowie der zu ihrer Herstellung geeigneten Hochtemperatur-Verdichtungstechniken, mit dem Ziel, einsatzfähige Tiegelwerkstoffe und -komponenten für eine industrielle Fertigung von einkristallinen AlN-Wafern zu entwickeln.

Die beschriebene Forschungsarbeit wurde durch das Zentrale Innovationsprogramm Mittelstand (ZIM) des Bundesministeriums für Wirtschaft und Technologie (BMWi) gefördert.

As part of the project, foam ceramics with adjustable porosity were originally developed at FCT as a graphite substitute for growing high-perfection, low-defect AlN single crystals. The work included the development of suitable technologies for the initial shaping of foam pre-bodies, their subsequent sintering as well as experiments on the variation of porosity and pore structure. The final foams of Tantalum nitride are free of carbon, have a high chemical and thermal stability in the range around 2200°C, a relatively high electrical resistance. They were also tested at the IKZ under conditions close to cultivation in order to evaluate the criteria necessary for their planned use of the ceramic as thermal insulation and graphite substitute.

High-performance machining of difficult-to-cut materials through hybrid ultrasonic-assisted cutting. Development of highly thermally conductive diamond-Si3N4 composites.