Overview
In high-temperature structures, electronic packaging, aerospace, and other fields, molybdenum alloys have become indispensable key materials due to their outstanding high-temperature strength, low coefficient of thermal expansion, and excellent thermal and electrical conductivity. However, within the molybdenum alloy family, significant performance differences exist among TZM (titanium zirconium molybdenum alloy), molybdenum-lanthanum alloys, and molybdenum-copper composites. Helping customers select the optimal material always hinges on the core requirements of the specific application scenario.
Understanding the Basics
- What is TZM alloy?
TZM alloy, a titanium-zirconium-molybdenum alloy, is a refractory alloy optimized by adding trace amounts of titanium, zirconium, and carbon to a molybdenum matrix. It retains molybdenum's high melting point and excellent thermal/electrical conductivity while significantly enhancing high-temperature strength and creep resistance. Additionally, it offers favorable room-temperature machinability and resistance to brittle fracture. Consequently, it is widely used in high-temperature components for aerospace applications (e.g., rocket engine nozzles), sputtering targets in the electronics industry, structural components in nuclear applications, and heating elements in high-temperature furnaces-all scenarios demanding exceptional heat resistance and structural stability.
- What is Molybdenum Lanthanum Alloy?
Mo-La alloy is a novel refractory alloy formed by dispersing trace lanthanum oxide particles in a pure molybdenum matrix. Its core advantage lies in leveraging the "dispersion strengthening" effect. While retaining molybdenum's high melting point and excellent thermal/electrical conductivity, it significantly enhances high-temperature creep resistance and structural stability. It also offers superior room-temperature toughness and machinability, alongside enhanced high-temperature oxidation resistance and weldability. It finds extensive applications in heating elements and structural components for high-temperature furnaces, high-temperature electrodes in the glass industry, load-bearing parts in aerospace, and precision components within the electronics and information sector that demand stringent high-temperature resistance and dimensional stability.
- What is the molybdenum copper composite material?
MoCu Alloy is a pseudo-alloy formed by combining molybdenum and copper through powder metallurgy (the two elements are immiscible and achieve only a physical bond). It retains molybdenum's high melting point, high strength, and low thermal expansion coefficient while possessing copper's excellent thermal and electrical conductivity. By adjusting the molybdenum-to-copper ratio, the material's thermal expansion coefficient and density can be precisely controlled. This enables thermal matching with dissimilar materials like chips and ceramics, preventing component damage from thermal stress. It is particularly suited for precision applications demanding stringent material properties: high thermal conductivity, low expansion, and dimensional stability.
Performance Comparison
| TZM合金 | Mo-La | Mo-Cu | |
| High temperature strength | It still maintains 400 MPa tensile strength at 600 ℃, and its recrystallization temperature is ≈ 1400 ℃, which is significantly higher than that of pure Mo. | Recrystallization temperature is ≈ 1500℃, La₂O₃ pins the grain boundaries, and the strength retention rate above 1100℃ is better than TZM | The copper matrix has a low melting point, and its high-temperature strength mainly depends on the Mo skeleton, which decays rapidly after ≥ 600 ℃. |
| Room temperature ductile-brittle transition | Better than pure Mo, but still brittle | The ductile-brittle transition temperature is the lowest (-50 ℃ level), and the cold-rolled sheet can be bent at room temperature | Depends on relative content; when Cu>30%, toughness is best, but strength decreases |
| Thermal conductivity and electrical conductivity | ≈ 120 W m⁻¹ K⁻¹, conductivity 30 % IACS class | Similar to pure Mo, slightly lower | Cu network continuous → thermal conductivity 180–220 W m⁻¹ K⁻¹, electrical conductivity 40–50 % IACS |
| Thermal expansion matching | 5.1×10⁻⁶ K⁻¹(RT–500 ℃) | 5.0×10⁻⁶ K⁻¹ | Adjustable to 6–10×10⁻⁶ K⁻¹, compatible with packaging materials such as Si, Al₂O₃, Cu, and Kovar |
| Machinability/weldability | Can be machined and electron beam welded, but tool wear is high | Good cold rolling performance, can stamp complex parts, and has a lower tendency to crack in TIG welding | Easy to machine; Cu phase improves machinability |
| Key processes |
The powder metallurgy process involves mixing molybdenum powder with titanium and zirconium compound powders, followed by pressing, sintering, and plastic working. During this process, titanium and zirconium react with carbon to form TiC and ZrC hard phases, which are uniformly dispersed throughout the molybdenum matrix while simultaneously inhibiting molybdenum grain growth. |
La₂O₃ particles are evenly dispersed in molybdenum powder through the "internal oxidation method" or "mechanical alloying method", and then sintered, rolled, or forged to form. It is easier to roll into thin strips and draw into fine wires. |
The mainstream approach employs either the "powder metallurgy composite method" (mixing molybdenum powder with copper powder → pressing → sintering → diffusion bonding) or the "electro-discharge plasma sintering process" to ensure uniform distribution of molybdenum particles within the copper matrix and prevent stratification. |
Adaptability of application scenarios
TZM: Due to its excellent high-temperature strength, high recrystallization temperature, and good thermal conductivity, it finds extensive applications in aerospace and aviation fields. Examples include nozzle materials, gas distribution valve bodies, gas pipeline materials, grid materials in electron tubes, X-ray rotating anode components, die-casting molds and extrusion dies, heating elements in high-temperature furnaces, and thermal shields. Simultaneously, it holds significant applications in nuclear power equipment and electronic components.
For instance, in the thermal zone of single-crystal furnaces (operating temperatures of 1300-1400°C), materials must maintain stable shapes without significant deformation at high temperatures. The TiC/ZrC strengthening phases in TZM alloy effectively resist grain boundary slip. Its creep fracture strength at 1200°C exceeds that of pure molybdenum by more than three times, while retaining sufficient toughness at high temperatures to prevent brittle fracture.
Molybdenum-Lanthanum: Suitable for vacuum furnace insulation screens, sintering boats, evaporator coils, and other components requiring long-term stability at temperatures below 1400°C. Its outstanding high-temperature stability and creep resistance enable excellent performance in these applications.
For plastic processing and medium-temperature scenarios (e.g., high-temperature molybdenum wire, electron tube cathode supports), molybdenum-lanthanum alloys are generally preferred. For instance, high-temperature molybdenum wire requires material capable of being drawn into filaments <0.1mm in diameter while resisting brittle fracture at elevated temperatures. Molybdenum-lanthanum alloy's La₂O₃ particles refine grain size, enabling cold working rates exceeding 80% (significantly higher than TZM's 50%) and achieving 15% elongation at room temperature, while meeting creep resistance requirements at moderate to high temperatures.
Molybdenum-Copper: Composed of molybdenum and copper, this alloy offers adjustable thermal expansion coefficients and high thermal conductivity. It is suitable for manufacturing passive cooling components (heatsinks) in electronic devices, microwave carriers, microelectronic packaging substrates and housings, laser diode bases, conductors for surface-mount packaging, and microprocessor covers. In the aerospace and aviation industries, its lower density also presents promising application prospects.
For instance, high-power LED heat spreader substrates require rapid dissipation of chip heat (to prevent thermal failure) while maintaining a thermal expansion coefficient close to the chip's to prevent cracking from thermal stress. Molybdenum-copper composites (e.g., 60% molybdenum, 40% copper) achieve thermal conductivities up to 250 W/(m·K) (1.8 times that of TZM), with thermal expansion coefficients perfectly matching chip-substrate thermal compatibility. They also offer lower costs than TZM and molybdenum-lanthanum alloys.
TZM Plate And Sheet
Molybdenum Lanthanum Tube
Molybdenum Copper Sleeve
Conclusion
TZM exhibits the most comprehensive performance characteristics, featuring outstanding high-temperature strength, high-temperature plasticity, creep resistance, and excellent thermal conductivity. It is suitable for applications under extreme high-temperature and mechanical load conditions, such as aerospace and nuclear power equipment.
Molybdenum-lanthanum alloys exhibit exceptional performance in high-temperature environments below 1400°C, characterized by a high recrystallization temperature and excellent creep resistance. They are suitable for components requiring long-term stability at elevated temperatures, such as vacuum furnace insulation screens.
Molybdenum-copper materials exhibit excellent thermal conductivity and a tunable thermal expansion coefficient. They are ideal for applications demanding efficient heat transfer, such as heat dissipation components in electronic devices, and also hold potential applications in the aerospace and aviation industries.
FANMETAL can produce various customized molybdenum alloy materials for you. If you have any questions about this product's details or delivery time, don't hesitate to get in touch with us at admin@fanmetalloy.com. We look forward to your message.
