Except controlling WC powder in grinding state, WC granularity distribution also has an importance effect on the uniformity of alloy grain size. If the WC powder particle size distribution is wide, which is quite different size, after grinding difference WC grain size will become bigger and bigger, its surface energy difference increases accordingly. In the process of sintering, dissolution and precipitation reaction becomes more remarkable and WC grain grows easily, which forms uneven alloy grain size. In other words, tungsten carbide button granularity depends on WC powder granularity distribution. Therefore, in the process of preparation, we should not only pay attention to the granularity of WC powder, the granularity distribution but also can not be ignored.

WC powder granularity and distribution in raw material is one of reasons that affecting tungsten carbide button granularity and distribution, ball milling process and its alloy ball also has an impact on the granularity finally. In the process of ball milling, the ratio of ball and material, ball milling time, the shape and quality of alloy ball are all the key influencing quality. Actually, alloy ball will be milled smaller and smaller, which indicates the part of milled get into the material. This means that it should be used in the alloy grain size and similar material prepared alloy ball can guarantee mixture size and uniformity.

Control alloy two-phase region refer to the same alloy grain size and the same Co content, the need to adjust the carbon content of the alloy, it is in between the two-phase region. Through confirm the total amount of carbon and the amount of free carbon to achieve more precise control of carbon, so that carburization and decarbonization phenomenon does not occur. It should be noticed that the choice of forming agent, degreasing sintering process of selection and to avoid direct contact with air to prevent oxidation, if necessary, purged with nitrogen during storage protection.

Tungsten carbide button has high hardness, high strength, high wear resistance and excellent chemical stability so that it can be widely used in oil field drilling, mining, offshore drilling. In these more complex demanding work environment, tungsten carbide button usually encounter hard rocks need to withstand high pull (pressure) stress, shear stress and shock loads, especially sometimes the higher or lower temperature will challenge the button, which will make it failure. The most important factor of tungsten carbide button failure is that the existence of fracture source.

So the corresponding failure improvements include that to choose WC powder similar to alloy granularity, to choose WC powder with uniform granularity distribution, to control the granularity of the ball in ball milling and to control the two phase area. Generally, tungsten carbide button used for oil field drilling granularity is in the range of 2.0-2.4μm, which needs to WC powder ground to the desired particle size by increasing ball milling time. However, the ball milling time can not be too long to cause part of WC powder ground extremely fine, which occurs WC intra-granular distortion, dislocation and the surface energy of WC will increase. In addition, only choose grinding state similar to WC powder under conventional milling time can we ensure the size to meet the requirements.

Radioactive substances mean the materials are capable of spontaneously decaying and emitting radiation energy. They are usually metals with high atomic energy, such as uranium and plutonium. Radioactive substances have many uses in various fields. In industry, they can be used for nuclear electric power generation, fracture detection of welding points and metal parts, static elimination, industrial X-ray detection and diameter measure; in agriculture, they can be used in plant breeding, sterilization and pest control and researching fertilizer uptake and loss; in medical applications, they can be used to diagnose and treat diseases; in the military, they can be used in nuclear weapons, nuclear submarines and nuclear fuel, operation teapot. Generally, the rays emitted by radioactive substances are α rays,β rays and γ rays which are all harmful for human body. So tungsten alloy is a best choice to store radioactive substances due to its great radiation shielding performance.

Radioactive substances can enter into human body through respiratory tract, the digestive tract, skin and mucous membrane, and continue to emit various rays inside body to induce internal exposure. Radioactive substances cause health problems by killing cells in the body, and the degree and type of damage done depends on the dose of radiation received and the time over which the dose is spread out. Receiving high doses of rays in a shorter time usually causes more acute damage, as greater doses kill more cells. Larger doses will, in addition to those symptoms above, cause hemorrhaging, sterility and skin to peel off; an untreated dose of more than 3.5 Sv will be fatal, and death is expected even with treatment for doses of more than 6 Sv.

Tungsten alloy container plays an important role in the storage of radioactive substances, it is often used to store the radioactive substances while shielding the radiation released from the radioactive substances. Early shielding material is mainly lead metal, but there are some problems in the long-term use of lead shielding. Lead and its compounds are harm to human body by causing poisoning. But tungsten alloy is non-toxic and has high density, thus it has great radiation shielding effectiveness to shield and absorb rays emitted by radioactive substances.

Tungsten alloy shielding for neutron logging is widely used in neutron logging. Neutron logging consists of a neutron source and a single detector. Many variations were produced utilizing both thermal and epithermal neutrons. In most of the early tools, neutrons were not detected directly. Instead, the tools count gamma rays emitted when hydrogen and chlorine catch thermal neutrons. Since hydrogen has the biggest impact neutron transport so far, the borehole effects on such tools are large. The now-standard compensated neutron-porosity logging tool is a very simple tool. Like a density tool, it consists of a neutron source and two neutron detectors. The tool surveys the size of the neutron cloud by identifying the decline of neutrons between the two detectors. Because neutrons have a much higher penetrating power than gamma rays, the design is much simpler than that of a density tool. It demands little collimation and does not need to be pressed against the borehole wall.

According to the different tools used in neutron logging, neutron logging can be divided into neutron-thermal neutron logging, neutron-epithermal neutron logging, neutron-gamma logging, neutron-gamma ray spectrometry log; while it can also be divided into conventional neutron log, compensated neutron log and sidewall neutron logging in accordance with the structural features of the tools. The neutron sources used by neutron logging are mainly isotopic neutron source and accelerator neutron source (now most often americium-beryllium, although at least one tool uses an accelerator source). Neutron radiation which is generated by the high-energy neutrons can damage personnel in the effective range, and cause blood-forming organ failure, digestive and central nervous system damage, as well as leukemia, cataracts and other diseases.

The neutron radiation and gamma radiation released during the process of neutron logging will harm human health. So it is generally recommended to use tungsten alloy shielding for neutron logging to shield the radiation to protect staffs from radiation damage. Tungsten alloy shielding for neutron logging has a high density. Because the radiation shielding effectiveness of a metal material will increase with the increasing of its density, thus the tungsten alloy shielding for neutron logging has good radiation shielding effectiveness. 

Tungsten alloy gamma knife, also called gamma-ray stereotactic treatment system, is a radiation treatment integrating directional technique with radiological technology to treat craniocerebral diseases and other diseases. The working principle of tungsten alloy gamma knife is collecting the gamma rays which released from the decay of Co60 radioactive element to irradiate the primary target in the body by the collimator to fatally destroy the target tissues, to cut and destroy a tumour. Instead of a scalpel, gamma rays can effective avoid the major tissues, and create an obvious boundary between a therapeutic irradiation range and normal tissues that likes a knife cutting, so people aptly called it "gamma knife". The biggest characteristic of tungsten alloy gamma knife is avoid the surgical operation to reduce the burden and risk of patients with intracranial tumor.

Tungsten alloy gamma knife to be divided into head gamma knife and body gamma knife. Head gamma knife can be used for the treatment of meningioma, pituitary tumor, neurofibroma, glioma, brain metastases, melanoma, craniopharyngioma, trigeminal neuralgia; while body gamma knife is used for treating general tumour, such as lung cancer, liver cancer, pancreatic cancer, adrenal tumors, kidney cancer, retroperitoneal tumor and pelvic tumors, Parkinson's disease, epilepsy, etc. Tungsten alloy gamma knife is a radioactive therapy. The rays it uses are gamma rays which have high killing ability to penetrate both normal tissues and tumor tissues, and the killing ability increases with the increasing of the irradiation scope and irradiation time. Gamma rays can also burn tissues and make them unable to repair themselves, then affect the tissues are not burned. During or after the process of radiotherapy, gamma radiation also lead to nausea and vomiting, alopecia areata, localized numbness, movement disorder and decline in platelets, white blood cells, pancytopenia, immune function and in severe cases can cause radiation sickness, such as radioactive myelitis, radioactive Japanese encephalitis. Therefore, tungsten alloy is usually used as the material of the metal shielding, fixed collimator, collimator helmets of gamma knife.

Some components of gamma knife  is made of tungsten heavy alloy for its' high density and good absorption of gamma radiation (such as a metal shielding, collimator, etc.). Since the density of tungsten alloy can reach so high, so it has a ideal radiation shielding effectiveness to shield and absorb gamma radiation, avoiding gamma rays killing the patient's normal tissues, to reduce the level of injury to the patient. And compared with other conventional shielding materials (such as lead), tungsten alloy is found no harm to people or the environment.

Tungsten copper sheet properties refer to phase analysis, micro-structure observation and other properties detection. The phase analysis can be specifically divided into DTA (Differential Thermal Analysis), XRD phase analysis (X-ray Diffraction), component test and so on. DTA uses differential thermal analyzer, the principle is to compare by not undergo any chemical reactions and physical changes at a certain temperature stable substance as a reference with an equal amount of measured (tungsten copper sheet) in the same environment under constant variable temperature conditions. Any physical and chemical changes on the measured and it is located in the same environment as compared to the standard temperature will be a temporary increase or decrease. The XRD phase analysis uses copper K radiation target, adjust current, voltage, and scanning rate, the measured characteristic X lines of tungsten copper sheet specimen major constituent phases.

For tungsten copper material, component test usually uses dilute nitric acid - hydrofluoric acid solution, which due to W will precipitate in nitric acid medium in the form of acid and separated from the Cu. Next ammonium hydroxide precipitate was dissolved tungstate, ammonium tungstate determination of tungsten burning gravimetric method; then inductively coupled plasma atomic emission spectrometry filtrate the residual tungsten, both of which add up to the total amount of tungsten. The process of micro-structure of tungsten copper sheet detecting is Sandpaper milling → Washing → Polishing (Al2O3) → Washing → Alcohol Cleaning → Drying → Detecting Sample.

The performance tests include density test, hardness test (Vickers hardness HV), resistivity (electrical conductivity) test, thermal conductivity test, coefficient of thermal expansion test and so on. Density test uses a classic method of drainage method of Archimedes; micro hardness is measured by the length of indentation of diamond indenter pressed into the surface of the sample; the resistivity usually uses bridge method; Thermal conductivity is the first on the surface of tungsten copper sheet sample sprayed on the surface of the toner in order to prevent the reflection of incident light, then at a certain temperature using the flash method thermal analyzer heating element xenon lamp emits a pulse beat in the sample surface, warmed by the infrared detector measures the situation was thermal diffusivity.

Due to tungsten copper material is composed of two kinds of metals with a great difference in melting point, which copper evaporates and takes off part of heat for equipments working well at high temperature. Especially in some electronic components with high power and easily heated, tungsten copper as heat sink has wide applications. However, with the rapid development of electronic science and technology, electronic components have become smaller and more precise, which places a greater demand on tungsten copper sheet and heat sine materials. Conventional process of tungsten copper sheet has some defects in thickness and density, so it is difficult to meet the requirements of the properties of heat sink materials. In order to fabricate tungsten copper sheet with uniform thickness and high density, the researchers study on three levels, which include continuous liquid phase sintering, cold rolling and re-sintering.

In the process of continuous liquid phase sintering, the preparation of raw material is also crucial. It should be noticed that the content of elements and granularity, the additives, the stirring time, the granulation process, drying temperature, forming pressure, blank density detection and many parameters controlling. Continuous liquid phase is conducted in molybdenum wire furnace under the protection of hydrogen. It puts tungsten copper sheet in the high temperature zone and holds a period of time, and then push to end cooled rapidly cooled to obtain the sintered sample. Afterwards, The sintered samples in the two-roll cold rolling mill and cold rolling deformation measurements, observed by optical microscopy that is rolling a longitudinal section (parallel to the rolling direction), the evolution of the cross-section (perpendicular to the rolling direction) of the microstructure. Finally, re-sinter tungsten copper sheet after cold rolling in the molybdenum wire furnace under the protection of hydrogen, and temperature should be controlled 1300℃ (above the melting point of Cu), in the high temperature zone without holding time in case of grain growth.