Sumitomo Metals Won a Commendation by the Minister of Education, Culture, Sports, Science and Technology, in the Development Category for Science and Technology, with its development of non-oriented electromagnetic steel sheet for high efficiency motors

On April 15, 2008, Sumitomo Metal Industries, Ltd. (Sumitomo Metals) received the Fiscal Year 2008 Commendation by the Minister of Education, Culture, Sports, Science and Technology(*2), in the Development Category for Science and Technology, for its development of non-oriented electromagnetic steel sheet for high efficiency motors(*1).

1. Object for commendation
The Commendation was given for non-oriented electromagnetic steel sheet which has superior magnetic properties and has been developed as a material for the iron cores of high efficiency motors, where energy saving, high torque, and downsizing of the motor are desired.

2. Details of the development
(1) Background and merits
In recent years, with the backdrop of climate change, compressor motors*3 for air conditioners and motors of hybrid cars have been required to achieve high motor efficiency, that enables conservation of energy, to be small in size so as to be capable of being mounted in a compact way, and to generate sufficient torque.

Non-oriented electromagnetic steel sheet developed by Sumitomo Metals enables these to be realized, and has been evaluated highly.

(2) Challenges of the development
To achieve energy conservation in high-efficiency motors, it is necessary to reduce loss that is generated when magnetism flows through electromagnetic steel sheet used for the iron core (iron loss).

At the same time, improvement of torque and downsizing of motors require raising magnetic power (magnetic flux density) of electromagnetic steel sheet.

Hence, the challenge in developing a high efficiency motor is to achieve both low iron loss and high magnetic flux density.

(3) Achieving low iron loss and high magnetic flux density
Iron loss indicates loss generated when a motor changes its electric energy to power. Such loss is consumed as heat, which causes a lowering of motor engine efficiency. An effective way to lower iron loss is to reduce sheet thickness.

Magnetic flux density indicates the strength of magnetism. Higher torque requires a raising of magnetic flux density; an effective way to accomplish this is to control the crystal alignment of the steel sheet. However, if sheet thickness is reduced in order to lower iron loss, it becomes difficult to control crystal alignment, resulting in lower magnetic flux density which in turn makes downsizing of a motor more difficult.

Sumitomo Metals, however, has established the world's first technology that enables control of crystal alignment of the electromagnetic sheet and a curbing of the reduction in magnetic flux density even when sheet thickness is reduced. This has been enabled by using the Company's special annealing facility and by raising the amount of phosphorus in the sheet, in order to achieve the normally opposed conditions of low iron loss and high magnetic flux density.

As a result, Sumitomo Metals has succeeded in developing unprecedented non-oriented electromagnetic steel sheet for high efficiency motors that enables low iron loss and high magnetic flux density at a high level.

3. Future development
At the same time that demand for motors has steadily become more challenging to manufacturers, the use of Sumitomo Metals' non-oriented electromagnetic steel sheet is expanding. This product has been highly evaluated in various circles: In 2007 it merited award of the Ichimura Industrial Prize by the New Technology Development Foundation, and in 2006 the Prize for Technology Development was awarded to the Company by the Japan Institute of Metals.

Sumitomo Metals will continue to respond to needs of customers by makings this technology widely available and strengthening its product line-up. At the same time, the Company sees this product as making a contribution to prevent climate change.

[Terms]
*1 Electromagnetic steel sheet
Electromagnetic steel sheet refers to steel sheet used as material for the iron core of an electromagnet. There are two kinds: grain-oriented and non-oriented.

Grain-oriented electromagnetic steel sheet excels in magnetic properties for a certain orientation but has weaker magnetic properties for other orientations. Thus, it is suitable to be used for iron core of a transformer where the magnetic orientation is specified.

In contrast, non-oriented electromagnetic steel sheet is inferior to grain-oriented electromagnetic steel sheet in magnetic properties for a certain orientation, but excels in magnetic properties regardless of the direction, meaning that direction does not affect its performance. Thus, it is best used when magnetic orientation is not specified, such as for the iron core for motors. The electromagnetic steel sheet Sumitomo Metals has developed is a non-oriented one.

*2 Commendation by the Minister of Education, Culture, Sports, Science and Technology
Japan's Ministry of Education, Culture, Sports, Science and Technology describes the purpose of the Commendation for Science and Technology by the Minister and explains the Development Category of Prizes for Science and Technology on its website, as follows:

[Purpose of the Commendation]
The Ministry of Education, Culture, Sports, Science and Technology has set up the Commendation for Science and Technology by the Minister. This is to award people for their distinguished achievement in research and development and promotion of understanding on scientific technology, with the purpose of encouraging people engaged in scientific technology and contributing to promote Japan's standards in science and technology.

[Explanation on the Development Category of Prizes for Science and Technology]
This category awards persons and institutions who have contributed to development and improvement of Japan's social economy and people's living and have conducted distinguished research, development or innovation.

*3 Compressor motor
A compressor has a structure incorporating a built-in motor within a pressure vessel and is an important component to compress and circulate a cooling medium that flows inside an air conditioner. The compressor is responsible for most consumption of electric power by an air conditioner and reduction of the energy use by its motor is an important issue.