The Metal Quality Analyzer (MQA™)
For years, inclusion analysis has been at the forefront of investigative work to determine castability issues and improve product quality. The control of inclusions relies on accurate knowledge about the phase changes and compositional relation of them under various chemical and thermal conditions during processing. Given the direct link between the inclusion content and steel production process, manufacturers of steel demand an analyzer that can operate under adverse conditions.
Take the Solution Out of the Lab and Into the Melt ShopThe ASPEX Metal Quality Analyzer; (MQA™) provides up-to-date inclusion compositional information on both lollipop, as cast, and final product samples. Routine improvement initiatives include:
- Tundish clogging and erosion minimization
- Nozzle clogging due to calcium aluminates or magnesium spinels
- Varying calcium additions to optimize castability
- Steel cleanliness versus casting time
- Comparison of inclusion content to standard analytical methods
- Degasser circulation and optimization
- Quality assessment of steel cleanliness
- Slab, billet or bloom disposition
- Alloy development
- Hardware changes, such as tundish linings and their overall effects
Once fully implemented through our support network, the MQA provides the necessary information that can result in savings of over $1,000,000 per year, whether through energy savings or consumable consumption.
Contact our specialist for a customized savings proposal.
Why is the ASPEX MQA™ Unique?Although SEM/EDX systems do an incredible job of examining inclusions of interest, routine quality control analysis can require tens of thousands of inclusions to be characterized and manual inspections can be time-consuming and inefficient. One way many companies are trying to automate the inspection processes is to use a 'frame-based' analysis, where a conventional scanning electron microscope (SEM) is used like a camera and automated via the energy dispersive spectrometer; however, using an SEM like a camera results in a fairly inefficient analysis process.
By comparison, the MQATM dynamically scan the sample through utilizing the electron microscope, not the EDX system. Rather than capturing a high-resolution image of the field, the system moves the beam across the field in an array of fairly coarse steps. At each point, the brightness of the backscatter signal is noted. If the signal is dark enough to indicate that an inclusion is present at that position, then the software initiates an inclusion-sizing sequence, RCA.
Save Time by Only Collecting Detailed DataThe 'rotating chord algorithm' (RCA) was chosen for both accuracy and its exceptional throughput. Once the “coarse” scanning identifies an inclusion, the center-mass is identified and chords are drawn with the beam on the inclusion to define its size and shape. Since the implementation of this analyzer is focused on process control and optimization, analysis times and report turn-around times are extremely important.
The major advantage in speed for the MQATM is because the instrument is controlled through a single computer (integrating both the electron beam and EDS acquisition). As a result, the MQATM only spends time collecting detailed data where inclusions are known to be present, rather than spending time capturing and analyzing vast numbers of “empty” information. Immediately after the inclusion is sized, the MQATM then captures an energy dispersive X-ray spectrum (200-500 milliseconds) and determines the elemental composition and inclusion typing based on characterization rule sets.
In addition to being fully integrated SEM/EDX systems, our SEMs are capable of counting, sizing, and determining elemental composition. The information directly reported by our analyzers is currently used throughout the industry to continuously control steel making practices and improve inclusion modification protocols.
Contact us to demonstrate how our analyzers are the fastest on the market, with scan speeds of up to 10,000 inclusions fully characterized in an hour, for routine production and research level inclusion analysis where accurate identification is required.