Recently, French Atomic Energy Commission (CEA) / Institute of magnetic confinement fusion (IRFM) researchers announced a good news: Institute of Plasma Physics, Chinese Academy of Sciences has made key progress in the development of two types of tungsten copper heat load (HHF) test module towards plasma components (W / Cu-PFC) test. Tungsten copper towards plasma component mainly refers to perforated tube. Tungsten copper perforated tube is one of the parts of vertical divertor target plates, and the divertor has been playing an significant role in magnetic confinement fusion reactor.

The main role of divertor is that the interaction between plasma and materials processing separated in two chambers and separates the resulting doping source and the main plasma. In general, it uses High heat load irradiation for the divertor properties testing, which is an important criteria to evaluate the quality of tungsten copper perforated tube. Tungsten copper not only has high melting point, high strength, low coefficient of thermal expansion, low sputter rate, low retention and excellent wear and corrosion resistance, etc., which is recognized as the most suitable for future nuclear fusion reactor plasma-facing materials. Tungsten copper perforated tube is first to drill on tungsten block, followed by brazing or hot isostatic pressing (HIP) block and other technology tungsten chromium zirconium copper pipe connected. Since it has symmetry in structure, can relief the thermal stress concentration and eliminate the stress point so that it can withstand high thermal loads irradiation.

Tungsten copper perforated tube fabricated by HIP has well combining face and without any obvious cracks, but the wall thickness of the circumferential unevenness in the HIP process of collapse and cracking phenomenon occurs. This time, the Chinese Academy of Sciences has made a major breakthrough in the manufacture of technology in the international community for the first time to achieve mass production of tungsten copper PFC, tungsten plasma interaction to carry out a comprehensive study under the conditions of long-pulse high parameters and provides an excellent platform. According to IREM researchers report relevant results: W / Cu perforated tube (Mono-block) No. 4 block modules withstand 1,200 times 10MW / m2 and 300 20MW / m2 radiation heat load; No. 5 tungsten block withstood 500 10MW / m2 and 500 20MW / m2 radiation heat load beyond the International Thermonuclear Experimental Reactor ITER to 20MW / m2 radiation heat load 300 requirements. In addition, W / Cu plates (Flat type) module FT1 to withstand 102 times 10MW / m2,102 times 15MW / m2 and 302 times 20MW / m2 radiation heat load; Tablet Module FT2 withstood 302 times 10MW / m2,102 times 15MW / m2 and 102 times 20MW / m2 radiation heat load. Irradiation results far beyond the flat module 5 MW / m2 in the ITER design requirements, refresh the W / Cu plate member is known recording HHF tests. This also proves that the advanced nature of the plasma connecting tungsten copper PFC technology to some extent.

A group of Chinese investors has offered €6 a share to buy Aixtron, valuing the German supplier of semiconductor equipment at about €670m, in the latest case of a mainland acquisition of a western industrial company.

Aixtron, which makes equipment used in LED lighting, said on Monday that it had agreed to a takeover by Grand Chip Investment, the German arm of Fujian Grand Chip Investment Fund. The Chinese group is controlled by Zhendong Liu, a Chinese businessman who owns 51 per cent of the fund. Xiamen Bohao Investment owns the remaining 49 per cent.

Under the terms of the agreement, Aixtron shareholders will be offered €6 in cash for an ordinary share, nearly 24 per cent more than Aixtron’s closing share price of €4.86 a share on Friday. The deal represents a 51 per cent premium over Aixtron’s three-month weighted average share price. Shares in the German equipment maker rose by more than 16 per cent on Monday after news of the agreement.

Aixtron said its legal domicile and headquarters would remain in Herzogenrath, Germany. It added that chief executive Martin Goetzeler and Bernd Schulte, chief operating officer, would remain in their jobs at the company.

Grand Chip Investment is expected to appoint four representatives to the Aixtron’s six-member supervisory board once the deal is complete. The takeover is still subject to shareholder approval and certain regulatory conditions being met.

Kim Schindelhauer, Aixtron chairman, said on Monday that the board members “fully support this transaction as it provides immediate value to our shareholders while also enabling Aixtron to bring their new products to market”.

The disappointing first-quarter results came just four months after the equipment maker suffered its worst day in 16 years upon losing its largest customer. Last December, Aixtron said Chinese client Sanan Optoelectronics had cancelled its orders, forcing Aixtron to cut its full-year sales guidance and sending shares down as much as 43 per cent in a single day.

Ammonium metatungstate used as the raw material of thin film substrate for semiconductor device will improve its property. Thin film grows on the substrate, the substrate material properties and characteristics of the substrate surface has a big impact on the film, because the film thickness is between nanometers to microns, the substrate surface is required for high flatness; The combination of film and the substrate is also a very important aspect, if the lattice mismatch, at the beginning of the film formation stage will form a long transition area. The wide application of semiconductor device makes ammonium metatungstate has a prospect market and is becoming an important material in emerging industry.

Thorium tungsten electrode is mainly used in DC negative electrode or carbon, stainless steel, nickel alloy, titanium alloy and other positive electrodes. Due to its good operating performance, even if it is suffer from overload current, it still in good operating. However, when AC welding electrodes by thoriated wolfram electrode, welding should be in a fast speed, and users should be careful to avoid direct current soldering react before AC soldering. When AC welding, ball balled will not melt, so its effect is not as good as a liquid ball.

Thorium is used as the main ingredients for thoriated tungsten electrode which exists in mineral in the form of the chemical compounds, and emits α particle. Mass of emitted α particles is much larger than that of the electron, atoms of material will ionize and lose energy by the time the α particle go through it, so its penetration ability is poor, its range is only a few centimeters in the air, as long as a piece of paper or healthy skin to block. Nevertheless, once they are inhaled or injected, it would be very dangerous, which can directly damage cells, tissues of giblets.

China is so far the only country in the world to produce radioactive tungsten electrodes. However, radioactive element is a physical carcinogen, which is likely to bring out gene mutations, resulting in that a normal proto-oncogene and anti-oncogene have mutation, finally cause the cancer cells. Due to varying degrees of radioactive contamination in its production and application, thoriated wolfram electrode withdraw from market is only a matter of time. China has stepped up the controls on thorium mining in a year and a half ago, prohibiting mining the thorium. Thus resulting in the production of material of thoriated wolfram electrode is not enough, the supply is not adequate to the demand, and price rose sharply. In addition, currently ranked second usage is cerium tungsten electrode, which does not produce radioactive contamination, and belongs to green products, it only need a very small current that it can easily arcing, and dimensional arc current is relatively small. At low current DC conditions, cerium tungsten electrode enjoys a great popular in the world. On the other hand, thorium is a potential nuclear fuel which is widely distributed in the earth's crust, and it is a promising energy materials in the future.