Researchers in Beijing Institute of Technology are exploring better ways to identify ionic optics by adding materials to make molybdenum components. Their results have recently been published in the paper “3D Printed molybdenum for grids and keeper electrodes in ion thruster”.

The main components of ion thruster are ion optics and protector. Optics plays an important role in the geometry of the engine. However, their erosion limits the life of ion thrusters. The purpose of the protector is to protect the hollow cathode from "ion bombardment" and turn on the cathode discharge. Metals and carbon materials are usually used to make the necessary electrodes. Molybdenum is a metal material commonly used in ion optics and conservative manufacturing.

Among carbon-based materials with near zero thermal expansion coefficients (CTE) and lower sputtering yield than molybdenum, graphite has become a conventional choice because of its low cost and high understanding of its manufacturing methods, although pyrolytic graphite and carbon-carbon composites have been used for many times in ion optical systems mounted on important thrusters, the researchers said.

In order to simplify the manufacture of ion optics system, a study was carried out by Beijing University of Technology, focusing mainly on the 3D printing of molybdenum on the parts of electric propeller. It is successful and still in the development stage. So far, several healthy electrodes have been produced. The researchers chose selective laser melting (SLM) for the project, mainly because of its ability to print metals and, of course, because of the level of accuracy it can provide, especially in aerospace. The commonly used metal materials are titanium, aluminum and stainless steel.

The research project of Beijing Polytechnic University has created several 3D printed ion optics components previously used in titanium to further study the concept of ion optics in the fabrication of additives. Another study measured energy density, involving: laser power; laser scanning speed; hatch spacing; layer thickness.

"The results show that the mechanical and thermal properties of SLM molybdenum are similar to those of solid metals when the energy density applied in the preparation process is close to the maximum energy density, thus producing refractories, i.e. about 300 Jmm-3. This fact is related to the porosity produced, which decreases with the increase of energy density. The researchers concluded. The sputtering corrosion behavior of selective laser melting materials has not been evaluated yet, but it must be studied before the components manufactured by the additives can meet the practical application of electric propulsion.

Analysis of latest tungsten market from Chinatungsten Online

Chinese tungsten prices are unchanged from the previous trading day on persistent weakness in the demand side and uncertain outlook of the market. Most market participants take a watchful stance, waiting for further directions from large tungsten companies and institutions. 

Rare earth market quotation in China: domestic rare earth price

China rare earth prices continue to show a downward trend in the week began on Monday July 15, especially for light rare earth elements. Owing to low trading activity of traders, capital shortage and no significant positive news, prices of light rare earth elements keep declining. Some medium-sized enterprises to sell the stock at low prices, but there are still many large enterprises stabilize the quotation.

China molybdenum prices stabilize but show signs of rise in the week ended on Friday July 26, 2019, thanks to active inquiry under the tightening availability of raw materials and increased demand of ferro molybdenum from steel mills. But both buyers and sellers still remain cautious sentiment. 

Analysis of latest tungsten market from Chinatungsten Online

The ferro tungsten and tungsten carbide powder prices in China are unchanged from the previous trading day on strong rised mentality of traders boosted by new round of environmental protection inspection but relatively low buying appetite of terminal buyers. 

Rare earth market quotation in China: the latest prices of terbium oxide, cerium oxide, dysprosium oxide and lanthanum oxide are still in the downward trend. Light rare earth market remains weak affected by the new round of environmental checks and output cuts of manufacturers. Medium and heavy rare earth market tends to stabilize, but same traders also sell products at low prices with the impact of capital pressure. 

Molybdenum market quotation in China: the latest prices of ferro molybdenum, molybdenum concentrate and molybdenum oxide climb slightly boosted by the short supply of raw materials and low inventories of downstream. 

Xiaomi company recently launched a tungsten carbide bead gel pen as a new product that is smooth, continuous and durable for writing, and the price is fair.

U.S. President Donald Trump on Monday ordered the U.S. Department of Defense to promote the production of large quantities of rare earth magnets for consumer electronics, military hardware and medical research, concerns that China would restrict exports.

Trump cited the 69-year-old Defense Production Act, once used to protect American steel-making capacity, to remedy what he called a "shortage" and to produce super-strong magnets made from rare earth minerals neodymium and samarium.

Trump issued a directive Monday that the ability of the United States to make magnets is "critical to national defense". Trump said that without action, U.S. industry "could not reasonably expect to provide production capacity for its products".

The Defense Production Act allows the President to prioritize contracts for materials, equipment and services in order to maintain or build domestic manufacturing capacity. It is used to force the purchase of semiconductor manufacturing equipment so that companies can produce military radiation-enhanced microelectronics - a niche market in which businesses may not invest themselves. It is also used to finance research and procurement projects in lithium-ion batteries, light ammunition and other technologies.

Trump’s June executive report said the United States needed a stable supply of key minerals to ensure its economic prosperity and defense. At that time, the Trump administration promised to take “unprecedented action” to ensure that the United States would not be disrupted by the supply of rare earths, a group of 17 minor but vital elements led by China.

Washington - The Department of Energy's National Nuclear Security Administration (DOE/NNSA) has completed negotiations on three cooperation agreement awards for the production of molybdenum-99 (Mo-99) without the use of highly enriched uranium (HEU). After selecting potential winners in February, the awards were negotiated and agreed with suppliers.

"Mo-99 is an important medical isotope that enables us to fight heart disease and cancer," said Lisa E. Gordon-Hagerty, director of the Department of Energy for Nuclear Security and NNSA. "These agreements will promote domestic production without the need for highly enriched uranium, greatly reducing the possibility of nuclear material proliferation."

Congress allocated $40 million to these incentives in fiscal year 2018 and $20 million in fiscal year 2019, and instructed the Department to issue a funding opportunity announcement to award cooperation agreements competitively. NNSA will fund each agreement at $15 million and require $15 million of matching funds for each awardee.

NNSA is supporting the establishment of surplus, reliable supply of Mo-99 produced in the US without the use of HEU. Mo-99 is used in more than 40,000 medical procedures in the United States every day, including the diagnosis of heart disease and cancer.

The American Medical Isotopes Production Act of 2012 directed the National Nuclear Security Administration to cooperate with non-Federal entities to implement technology neutrality programs. The technology neutrality plan is open to all methods of producing Mo-99 and does not use highly enriched uranium.