Other metals/rare metals
Other than tungsten and molybenum, we are processing many kinds of rare metals and metals.
1. Platinum
Platinum ring. Popular material for accessory.
Overview
Platinum is one of densest metals of all. It is chemically stable, and has excellent acid resistance and corrosion resistance. Variety of uses of platinum include filament for Pirani gauge, catalizerfor automobile exhaust. It is also used as brasing material. Platinum is less likely to cause metal allegy to people. Other than quite commonly used for accessory, it is widely used as material for various medical parts.
We mainly process platinum for gas sensor filament and coil for medical use. Generally these filaments and coils are extremely small. We form these small coils in various shapes and sizes.
Physical characteristics
| Unit of measurement | Content | |
| Atomic Number | 78 | |
| Standard Atomic | 195.084 | |
| Crystal Structure | Face-centered cubic | |
| Melting Point | Elementary substance | 1768℃ |
| Boiling Point | Elementary substance | 3825℃ |
| Density | g/cm3 | 21.45 |
| Electrical Resistivity | nΩ·m | 105（20℃） |
| Thermal Expansion | µm/(m·K) | 8.8（25℃） |
| Young's Modulus | ＧＰａ | 168 |
| Mohs Hardness | 4-4.5 | |
| Vickers Hardness | ＭＰａ | 549 |
| Rigidity | ＧＰａ | 61 |
| Poisson Ratio | 0.38 | |
| Magnetic Properties | Paramagnetism |
Example of using platinum
Platinum coil for analytical device（Welded coil)
Material information on other pages
2. Rhenium
Rhenium ribbon Outer case
Overview
It is considered very precious as it is one of rare metals with very low production quantities. It is the heaviest metal among single element, and density is higher than tungsten. It is one of ideal metals for use under extremely high temperature. We coil rhenium as electron source for analytical device, or we can supply rhenium filament after assembling to molybenum or tantalm support rod.
Physical characteristics
| Unit of measurement | Content | |
| Atomic Number | 75 | |
| Standard Atomic | 186.207 | |
| Melting Point | Elementary substance | 3186℃ |
| Boiling Point | Elementary substance | 5596℃ |
| Density | g/cm3 | 21.02 |
| Electrical Resistivity | nΩ·m | 193（20℃） |
| Thermal Expansion | µm/(m·K) | 6.2 |
| Young's Modulus | ＧＰａ | 463 |
| Mohs Hardness | 7.0 | |
| Vickers Hardness | ＭＰａ | 2450 |
| Rigidity | ＧＰａ | 178 |
| Poisson Ratio | 0.3 | |
| Magnetic Properties | Paramagnetism |
Example of usng rhenium
Rhenium coil for analytical device. (0.1mm coil diameter, 0.8mm coil length)
Material information on other pages
3. Niobium
Niobium wire
Overview
Although Niobium is one of higher melting point metals, it is relatively easy to process as it is malleable and flexible. In general, Nb is used as iron and steel additives. Here at Takeishi, we use this for one of parts for ceramic metal halide lamp electrodes, after adding 1% of zirconia. Due to the fact thermal expansion coefficient of niobium and ceramic arctube is close, we use niobium as sealing material. Niobium has a function of getter, and it absorbs moisture and hydrogen, lot of attention need to be paid when handling.
Physical characteristics
| Unit of measurement | Content | |
| Atomic Number | 41 | |
| Standard Atomic | 92.90638 | |
| Crystal Structure | Body-centered cubic lattice structure | |
| Melting Point | Elementary substance | 2477℃ |
| Boiling Point | Elementary substance | 4744℃ |
| Density | g/cm3 | 8.57 |
| Electrical Resistivity | nΩ·m | 152（0℃） |
| Thermal Expansion | µm/(m·K) | 7.3 |
| Young's Modulus | ＧＰａ | 105 |
| Mohs Hardness | 6.0 | |
| Vickers Hardness | ＭＰａ | 549 |
| Rigidity | ＧＰａ | 38 |
| Poisson Ratio | 0.4 | |
| Magnetic Properties | Paramagnetism |
Exsample of using niobium
Niobium pin (1% of Zr added)Because it is before heat treatment, it looks dark or greyish.
Material information on other pages
4. Tantalum
Tantalum plate and tantalum parts (trial manufacturing)
Overview
Tantalum has an excellent property of heat resistance, corrosion resistance and acid resistance. It is very rare and expensive material, that also has a function of getter. It is chemically and physically stable metal that has less impact on human body, and can be used as allegy, and can be used as medical parts like inplant and artificial bone.
We use this material as parts for analytical device, medical parts, and electron beam gun.
Tantalum is not very easy to machine, but here at Takeishi, we do micro machining tantalum.
Physical characteristics
| Unit of measurement | Content | |
| Atomic Number | 73 | |
| Standard Atomic | 180.94788 | |
| Crystal Structure | Body-centered cubic lattice structure(α-Ta) | |
| Melting Point | Elementary substance | 3017℃ |
| Boiling Point | Elementary substance | 5458℃ |
| Density | g/cm3 | 16.69 |
| Electrical Resistivity | nΩ·m | 131（20℃） |
| Thermal Expansion | µm/(m·K) | 6.3（25℃） |
| Young's Modulus | ＧＰａ | 186 |
| Mohs Hardness | 6.5 | |
| Vickers Hardness | ＭＰａ | 873 |
| Rigidity | ＧＰａ | 69 |
| Poisson Ratio | 0.34 | |
| Magnetic Properties | Paramagnetism |
Material information on other pages
5. Iridium
One of the most densest metals with extremely high melting point and hardness. It is known that iridium is one of the most difficult metals to process under room temperature. It is highly corrosion and abrasion resistant, and used for jewelry. We use this iridium for filament of analytical device electron source.
Physical characteristics
| Unit of measurement | Content | |
| Atomic Number | 77 | |
| Standard Atomic | 192.217 | |
| Crystal Structure | Face-centered cubic | |
| Melting Point | Elementary substance | 2466℃ |
| Boiling Point | Elementary substance | 4428℃ |
| Density | g/cm3 | 22.56 |
| Electrical Resistivity | nΩ·m | 47.1（20℃） |
| Thermal Expansion | µm/(m·K) | 6.4（25℃） |
| Young's Modulus | ＧＰａ | 528 |
| Mohs Hardness | 6.5 | |
| Vickers Hardness | ＭＰａ | 1760 |
| Rigidity | ＧＰａ | 210 |
| Poisson Ratio | 0.26 | |
| Magnetic Properties | Paramagnetism |
Example of using this material
Iridium mico coil for analytical device
Material information on other pages
6. Titanium
Titanium golf club.
Overview
Titanium oxide is well known as material for photocatalist. Titanium is widely available element. Under atmosphere, pure titanium forms minute and hard oxide film. High corrosion resistance is maintained after surface scratch, as oxide film self repairs the surface.
It is highly biocompatible, and easy to assimilate to human bones. It is widely used for medical parts as it is less likely to cause allegy to human body. Since it is very high in rigidity, but low in density, titanium is an ideal material for golf club head and airplane parts.
Physical characteristics
| Unit of measurement | Content | |
| Atomic Number | 22 | |
| Standard Atomic | 47.867 | |
| Crystal Structure | Face-centered cubic | |
| Melting Point | Elementary substance | 1668℃ |
| Boiling Point | Elementary substance | 3287℃ |
| Density | g/cm3 | 4.506 |
| Electrical Resistivity | nΩ·m | 420 |
| Thermal Expansion | µm/(m·K) | 8.6（25℃） |
| Young's Modulus | ＧＰａ | 116 |
| Mohs Hardness | 6.0 | |
| Vickers Hardness | ＭＰａ | 970 |
| Rigidity | ＧＰａ | 44 |
| Poisson Ratio | 0.32 | |
| Magnetic Properties | Paramagnetism |
Example of using titanium
Titanium dental implant
Material information on other pages
7. Nickel
Nickel wire
概要
Its melting point is point is still low when compared to extremely high melting point metals like tungsten and molybdenum, nickel has a quite high melting point of 1453℃, and has excellent property of heat and acid resistance. It is very ductile and is very easy to be alloyed. Here at Takeishi, we use nickel for lead wire for lamps, and Ni-Ti alloy for catheter. Nickel powder is oftenly used as additive metal for heavy alloy.
Physical characteristics
| Unit of measurement | Content | |
| Atomic Number | 28 | |
| Standard Atomic | 58.6934 | |
| Melting Point | Elementary substance | 1455℃ |
| Boiling Point | Elementary substance | 2913℃ |
| Density | g/cm3 | 8.908 |
| Electrical Resistivity | nΩ·m | 69.3（20℃） |
| Thermal Expansion | µm/(m·K) | 13.4（25℃） |
| Young's Modulus | ＧＰａ | 200 |
| Mohs Hardness | 4.0 | |
| Vickers Hardness | ＭＰａ | 638 |
| Rigidity | ＧＰａ | 76 |
| Poisson Ratio | 0.31 | |
| Magnetic Properties | Ferromagnetism |
Example of using nickel
Welded parts (nickel and molybdenum)
Material information on other pages
8. Other materials.
Some of other materials we often use are below.
8-1. Ni-Ti alloy
Nickel-titanium wire
Coil made of Nickel-titanium wire
Overview
Equal corrosion resistance and abrasion resistance to titanium, nickel-titanium has very high shape recovering force. We use this for guide wire and guide coil for catheter.
8-2. Kovar
Kovar pin used after forming to seal hard glass and other materials.
Overview
Kovar consists of 54% of Fe, 29% of Ni, and 17% of Co. As thermal expansion coefficent of kovar is low under normal temperature, it is widely used to seal hard glass material. For almina base support, we use kovar for EB gun, a core part for analytical device.
8-3. Stainless Steel
SUS304 wire, widely used for coils for medical use
Overview
For medical equipment, automotive, kitchen equipment, stainless steel has various uses. We often use SUS304 together with Ni-Ti alloy for guide wire for medical use.
8-4. Ceramics
Almina powder
Overview
Because its electric insulation properties, and heat resisting properties, ceramic is an ideal material for EB gun base and lamp filament base.
At Takeishi, Ａｌ２Ｏ３(Alumina), is oftenly used. It is a generic name for aluminum oxide, and is the final oxidization form of aluminum. Since it is very hard, highly heat resitive, electical resistive and chemically stable, it is used for abrasive, heat resistance material, anti abrasive and catalizer for automotives.
After mixing alumina powder and molybdenum powder, we make sintered cermet as lamp parts. We also use our sintered parts as base of EB gun. We can also braze or metalize metal materials to ceramic parts.
Aluminum crucible and setter used during sintering process
8-5. Polyester copper
Polyester copper wire
Overview
Magnetic wire made of copper coated by polyester. Coil for electric parts.
Polyester copper wire coil
