A client required spherical molybdenum-copper (Mo-Cu) alloy powder for an essential part 3D printing. The conventional methods, however, could not replicate the required morphology due to the pseudo-alloy and high-viscosity nature of the material. Stanford Advanced Materials (SAM) innovatively selected an ultra-fine raw material spray drying + controlled heat treatment process and ultimately obtained spherical Mo-Cu powder that met the customer's requirements for part printing materials.

SAM Provides Tailored Spherical Mo-Cu Alloy Powder Solutions

--Challenge: Molybdenum and Copper Cannot Fully Dissolve

One of the clients in a specific industry required high-performance spherical Mo-Cu alloy powder to 3D print the main components. However, Mo-Cu is a pseudo-alloy (Pseudo Alloy), and the two metals can't fully dissolve into each other. Traditional production techniques resulted in severe defects:

• Morphology Control Challenges: High viscosity of the material in the molten state led to poor flowability during powder formation, resulting in a lack of sphericity and smoothness, affecting the density and mechanical properties of printed parts.
• Low Process Adaptability: Powders from most suppliers had non-uniform particle size distribution or composition segregation, failing to meet the material consistency and reliability demands.

The client needed a solution that would ensure performance while achieving high uniformity and sphericity in Mo-Cu alloy powder.

--Solution: SAM’s Customized Process Achieves Semi-Fusion Breakthrough

SAM is experienced in large-scale manufacture of specialty powders. We've created a carefully designed multi-step process. SAM initially utilizes high-purity molybdenum and copper powders as raw materials. The powders' particles are extremely small, ranging from 0.5-3 microns. This guarantees uniform distribution in the final product.

Under closely controlled conditions, the liquid mix is converted into dry powder by advanced spray drying technology. Tight control over atomizer speed and liquid feed rates during this process leads to powder particles with nearly flawless spherical morphology.

Finally, SAM heat treats the composite powder. This critical step has two major advantages: it removes excess binders while, concurrently, hardening and rounding the powder particles.

--Results

After rigorous material testing and printing verification, SAM's spherical Mo-Cu alloy powder fully met the customer's specifications:

• Improved Printing Performance: Near-spherical particles enabled high packing density and uniform powder spreading, reducing porosity defects in 3D printing.
• Critical Properties Met: Compositional uniformity, thermal conductivity, and thermal shock resistance all satisfied industry specifications.

Microscope photo of molybdenum copper powder

What is a Pseudo Alloy

A pseudo alloy is a metal-matrix composite material wherein two or more metals exist as distinct, uniformly dispersed phases without the formation of an alloy phase. This material was created in the 1930s, and tungsten-silver (W-Ag) and tungsten-copper (W-Cu) alloys—produced by powder metallurgy—were among the first uses. These alloys consist of a tungsten matrix containing 20–50% silver or copper and are applied as contacts in high-power, high-voltage electrical switches.

In the pseudo alloys, the silver or copper in the capillary pores of the tungsten matrix evaporates and melts under the high temperature generated by electric arcs, consuming great amounts of arc energy and reducing the temperature in the arcing zone. These pseudo alloys thus possess much smaller erosion rates compared to pure copper or silver contacts, and even smaller compared to pure tungsten.

Characteristics of Molybdenum-Copper Alloy Powder

Molybdenum-copper (Mo-Cu) alloy powder is a high-performance pseudo-alloy material that combines the advantages of the two metals. Molybdenum's high melting point provides the composite with excellent structural stability at high temperatures, while copper provides excellent thermal conductivity.

The main features are:

• Excellent Thermal Expansion Matching: The coefficient of thermal expansion (CTE) can be controlled to match ceramics and semiconductors and is applicable to electronic packaging.
• Outstanding Thermal Shock Resistance: The alloy withstands thermal shock cracking under sudden temperature changes, meeting strict industrial and military applications.

Submit Requests to SAM

To meet specific 3D printing part requirements, SAM offers customized tungsten-copper (W-Cu), molybdenum-copper (Mo-Cu), and other spherical powders. SAM also supplies high-purity fine metal powders, including tungsten (W), copper (Cu), silver (Ag), and molybdenum (Mo).

Inquiry to Stanford Advanced Materials

Reference

What is Tungsten-Copper Alloy Powder Used for

3D Printing Powder: What is it & How is it Used?