Project outline

Overview

The aim of this project is to standardize the quantitative magneto-optical indicator film-based technique for spatially resolved magnetic field measurements (qMOIF) that was developed in the EMPIR project 15SIB06 Nanomag. The project will provide concrete advice how to make best use of the standardized qMOIF technique for characterizing micromagnetic materials by publishing a best practice guide including worked examples. A qMOIF Technical Specification will be submitted to the IEC TC 113 as a new sub-document of the existing standard “62607-9-1: Nanomanufacturing – Key Control Characteristics – Part 9-1: Spatially resolved magnetic field measurements – Magnetic Force Microscopy”. This will complement the existing standard and will significantly enhance its applicability range, particularly in industry. 

Need

Industrial users need traceably quantitative characterization tools for magnetic materials on the micrometre to centimetre scale to perform ISO 9001 compliant quality management of their products and production processes. To address this need, EMPIR project 15SIB06 Nanomag for the first time established high-resolution magnetic field measurement techniques, culminating in a quantitative magnetic force microscopy (qMFM) based field measurement standard. While qMFM can be regarded as the gold standard for nanoscale magnetic field measurements with extremely high spatial resolution, its technical application is often hindered by several drawbacks: qMFM is slow, has a limited imaging area and can only deal with samples flat on a 100nm scale. On the other hand, established NMR based SI standards for magnetic field measurements can only be applied to centimetre scale macroscopic objects. This leaves a gap on length-scales from micrometres to millimetres, where no standardized measurements are available. However, industrially relevant magnetic materials like precise magnetic encoders and     high-quality electrical steel sheets often combine micrometre scale magnetic features with sample dimensions in the millimetre range and show rough surfaces, leading to a poor applicability of the qMFM based standard to many industrially relevant materials. The primary supporter of this project, IEC TC 113, sees the need to bridge the standardization gap to such industrial applications as part of its overall aim of ensuring the standardization of the technologies relevant to electrotechnical products and systems in the field of nanotechnology.


qMOIF is a fast (sub second resolution) imaging technique that allows a one-shot characterization and thus high throughput of samples with areas of several square centimetres. Additionally, it can be used under harsh environmental conditions and for rough samples without the need for surface treatments. The EMPIR project 15SIB06 NanoMag established and validated qMOIF techniques with the capability to detect fields from the mTesla to the Tesla range with sub µm spatial resolution.  Accordingly, to amend the existing qMFM standard to include a TS for traceable qMOIF and to provide guidance to end-users how to use qMOIF to measure relevant material parameters, the IEC TC 113 introduced the Preliminary Work Item: PWI 113-128, IEC TS62607-9.2 -Nanomanufacturing – Key Control Characteristics - Part 9-2: Traceable spatially resolved nano-scale magnetic field measurements - Magneto-optical indicator film technique.

Objectives

The overall goal of the project is to incorporate the qMOIF measurement technique developed and validated within the EMPIR project 15SIB06 NanoMag into the existing IEC standard on nanoscale field measurements and to embed it into the industrially relevant metrological framework. 


The project addresses the following objectives:

  • To embed qMOIF into the existing normative framework. This will entail (a) defining the applicability range of qMOIF, (b) establishing a unified vocabulary including Key Control Parameters (KCPs), (c) defining unified terms and definitions describing the measurement and analysis process, and (d) identifying typical industrially relevant parameters and relating them to the MOIF KCPs. 
  • To provide written advice and guidance to end users in the form of a Best Practice Guide for qMOIF including worked examples. To extend the existing standard in nanoscale magnetic field measurements to the micro- and centi-metre-scales by drafting a Technical Specification for qMOIF and submitting it to the IEC TC 113.
  • To ensure a high awareness of the standard in the scientific and industrial communities. 

Results

The expected results in relation to the four objectives are: 

  • A unified qMOIF terminology. 
  • A Best Practice Guide for qMOIF including worked examples. 
  • The preparation and successful submission of a Technical Specification for qMOIF to the IEC TC 113 as a sub-document to the existing standard series. 
  • A high awareness and uptake of the new standard. 

These results align directly with identified end user needs, who require calibrated quantitative measurements and specific guidance on how to apply the outputs of JRP 15SIB06 to their specific measurement needs; to measure fast and reliably micro- and millimetre scale magnetic field distributions of industrially relevant materials; to relate their secondary material parameters to quantitative magnetic field data and thus to the SI system to demonstrate ISO 9901 compliance; to define their measurands in a widely agreed on unified terminology; to be able to identify the suitable qMOIF setup design depending on their material parameters.

Impact

The IEC TC 113, the SIP Primary Supporter, aims at standardization of the technologies relevant to electrotechnical products and systems in the field of nanotechnology. By incorporating the qMOIF technique into an existing series of IEC Technical Specifications under IEC TC 113 and by defining a unified vocabulary, this project addresses both the standardization of the nanomagnetic measurement techniques and of the nomenclature, and thus directly supports the strategic objectives of the Primary Supporter. 


The EMPIR project 15SIB06 NanoMag developed traceable calibration procedures for qMOIF. This project extends the outputs of NanoMag into a Best Practice Guide and into technical specifications for qMOIF based magnetic field measurements. Traceable qMOIF based calibrations will close the measurement and standardization gap for field measurements on the micrometre to centimetre length scale. Thereby, the project outcomes will open a path towards reliable, robust, quick and cheap characterizations of a large number of industrially relevant innovative magnetic materials and components. 


The outcome of this project will directly facilitate the uptake of the traceable qMOIF field measurement technique by industrial users via a standardized measurement approach referring to relevant parameters using terminology common to end-users and by providing guidance for the complete measurement process. Examples are measurements on magnetic encoders and steel sheets.


Magnetic encoders
Magnetic encoders are the central element of highly accurate and rugged magnetic positioning systems with resolutions competitive to interferometers but at significantly lower cost and suitable for applications under harsh environmental conditions as for example in the automotive and machine tool sector. Standardized magnetic microscale measurements as provided by this project will contribute to significantly enhanced positioning accuracies down to the sub-micrometre scale and will open new encoder application areas. 


Steel sheets
Electrical steel is a mass product which is used in many industrial sectors and whose demand is constantly growing. Conventional non-imaging characterizations using Epstein frames and single sheet testers, however, only measures the material integrally which is not sufficient from a technical point of view. Developers, manufacturers and users need to know how perfectly grain-oriented electrical steel is in the respective application and why problems occur. However, until today the industry is not able to check the domain structure in static and alternating fields by a standardized test method. qMOIF can close a technical gap here because the technology enables high-resolution and areal domain visualization. 


This project will 

  • provide traceable of microscale magnetic measurements to European industry and R&D labs and thus support a rapid development and adoption of innovative nano-magnetic technologies;
  • define standards for micro-scale magnetic measurements to underpin international harmonization and mutual recognition of worldwide micromagnetic measurements and devices.


A major goal of the EU is a 32.5% increase of energy efficiency and a corresponding reduction of greenhouse gas emissions by 2030. High-quality electrical steel sheets for low-loss conversion generators and for efficient power generation will lead to an increased energy conversion efficiency in utility transformers, wind turbines and motors including electric cars. Additionally, improved magnetic sensor technologies will help to further improve the efficiencies of non-electric motors, which for many areas cannot be replaced by electrical technologies in the foreseeable future.