Thanks to our unique combination of lab metal processing equipment and advanced characterisation methods, OCAS can offer its metallurgical expertise also during the development of complex multi-component systems.
Cast, shape and fully characterise complex multi-component systems
Customers interested in complex multi-component alloys, can benefit from OCAS service offer for casting, rolling, heat treatment and characterisation: from initial high-throughput screening all the way up to upscaling of the most interesting alloy.
Examples of multi-component alloys, for which OCAS delivered cast and rolled material to its customers, comprise metallic glasses and high entropy alloys. Both are complex multi-component alloys, typically containing four elements or more. Metallic glasses (BMG) form an amorphous structure, whereas high entropy alloys show a very simple microstructure.
Following the customers preferences, OCAS can investigate and screen these alloys, using its high-throughput methodology to fine-tune composition or merely develop the metallurgical concept for casting and rolling master alloys for further R&D purposes at the customer.
In addition to quick properties screening tests, such as non-destructive measuring the glass forming ability of BMGs, OCAS has experience in in-depth advanced characterisation analysis:
- Differential scanning calorimetry (DSC)
- XRD, including high temperature XRD
- Scanning electron microscopy: FEG-SEM and W-SEM
- Transmission electron microscopy (TEM)
- Atom probe tomography (APT)
- Advanced mechanical characterisation, including wear testing
- Corrosion testing, including electrochemical measurements
- Magnetic characterisation
Today, OCAS has the know-how to cast, shape and fully characterise complex multi-component systems for its customers.
“Thanks to our unique combination of lab metal processing equipment and advanced characterisation methods, OCAS can offer its metallurgical expertise also during the development of complex multi-component systems”
The scientific paper “Processing a Fe67Mo4.5Cr2.3Al2Si3C7P8.7B5.5 metallic glass: Experimental and computed TTT and CCT curves”, has been accepted for publication in Journal of Alloys and Compounds . This work was done by OCAS in close collaboration with Dipartimento di Chimica & NIS, Università di Torino (Italy). Authors: Alberto Castellero, Gianluca Fiore, Nele Van Steenberge, Livio Battezzati. Article number: 156061;Reference JALCOM_156061; PII S0925-8388(20)32425-7
For metallic glass synthesis and processing the possible formation of crystals should be described by CCT curves. Motivated by results of the synthesis of wires of the Fe67Mo4.5Cr2.3Al2Si3C7P8.7B5.5 alloy by melt extraction, a methodology is proposed to compute TTT and CCT curves based on the classical nucleation and growth theory. The thermophysical parameters needed for the calculation are entirely derived from DSC experiments, including those expressing the Vogel-Fulcher-Tammann equation for viscosity. The critical cooling rate for amorphous wires is estimated and matched with the CCT curve. Then, the corresponding computed TTT curve is shown to reproduce well the experimental results of isothermal crystallization of the ribbons.
In 2017, a presentation was given by OCAS at the RQ conference in Leoben on “Thermomechanical processing of FeCoCrNi(Mn, Al) high entropy alloys.