Author: Jamie

Read about the benefits of carbide tools for cutting and machining magnesium.

Magnesium is the lightest commercially available structural metal and exhibits excellent machinability. It has unique characteristics and requires just 55% of the power needed for machining aluminium.

It is safe and recommended to use carbide tooling on magnesium alloys.  Best practice for machining magnesium alloys should be followed, keep a look out for further articles on this topic.

Machining magnesium versus aluminium

Tool ranges used during the machining of aluminium can also be used for magnesium. These give satisfactory results. However, due to the free-machining characteristics, relatively low cutting pressures and slightly lower heat capacity of magnesium, best machining practice should take tool material, tool life and tool geometry into consideration.

Cutting speeds and tool stability

The potential for high-speed machining of magnesium alloys is usually only limited by the stability of the component in the clamping device, chip extraction or the rotation speed or accuracy limits of the cutting tool or machine.

The mean specific cutting force (ks1.1) of magnesium is 280 N/mm2 (40.61ksi), much lower than that of aluminium (approx. 640 N/mm2 (92.82 ksi). The result of this means that there is a reduced load on the cutter and tool body allowing higher cutting speeds and feed rates.

Benefits of carbide tooling

Higher speeds can be enjoyed with the use of carbide tooling, although HSS tooling can be used and is often employed in twist drills, taps and broaches. Carbide is the preferred tooling material for most machining operations on magnesium alloys.

Carbide gives a balance of economics and the ability to perform high volume production runs. Carbide tools offer the following advantages for machining magnesium:

• Gives a good surface finish
• Wear resistant
• Eliminates the occurrence of built-up edge (BUE) on the tool
• Uncoated carbide tools allow for sharper cutting edges
• Less costly that PCD

Tool geometry can aid efficiency

In order to take advantage of the machining characteristics of magnesium it is useful to consider recommended tool design and angles. The geometry of the tool can have a large influence on the machining process.

Tool geometry can be used to aid with:

• Chip flow and clearance
• Reduce excessive heat generation
• Reduce tool build up
• Enable greater feed rates to be employed
• Improve tool life.

Luxfer MEL Technologies offers a wide range of machined magnesium products. We’d love to hear about your applications and discuss how our materials can offer you a solution.

The highest mechanical strength and fracture toughness

Zirconium Oxide (ZrO2), also known as Zirconia, boasts the highest mechanical strength and fracture toughness compared to alternative fine grained ceramics. It exists in its monoclinic polymorph at room temperature and used in applications including ceramics and refractories due to its excellent thermal insulation properties.

Properties of Zirconium Oxide

The properties of Zirconium Oxide powder is dependent upon the process route used to produce the material. Chemically derived it’s consistent, highly homogeneous and the textural properties carefully controlled. Particle size, surface area and purity are tailored to meet the designated application.

It is also a highly versatile material when combined with other elements. Addition of Yttrium Oxide, Magnesium Oxide, Aluminium Oxide and others can enhance the mechanical, optical or thermal properties of the ceramics produced.

What is Zirconium Oxide used for?

Zirconium Oxide (ZrO2), also known as Zirconia, is used in a wide variety of applications across a number of markets.

Zirconium Oxide is also a highly versatile material when combined with other elements. A small addition of yttrium oxide unlocks the tetragonal polymorph and further enhances the mechanical properties and form materials suitable for advanced ceramic applications. Further addition of yttrium oxide yields the cubic polymorph and leads to function ceramics which conduct oxygen ions and used in sensors along with cubic zirconia for jewellery.

Luxfer MEL Technologies offers a wide range of Zirconium Oxides and Yttria Stabilized Zirconium Oxides. We’d love to hear about your applications and discuss how our materials can offer you a solution.

Lightweight materials for the motorsport industry

Today we think of aluminium as the go to lightweight material, but what if we told you there is a material which is 30% lighter than aluminium? Perhaps top tier motorsports best kept secret is the use of magnesium alloy technology to enhance performance of components through light weighting. As the world works to reduce emissions and increase performance of vehicles lightweight materials such as magnesium may play a key role.

Light weighting of components has many benefits: increased acceleration, reduced braking distance, reduction of emissions, fuel consumption, increased payloads, and increased range.

High specific stiffness

For bars with equivalent weight and width, magnesium is 18 times stiffer than steel and double that of aluminium. In practice it is not always possible to increase section thickness to these extents.  With only small increases in cross section it is possible to redesign parts that offer 20–25% weight savings over aluminium equivalents and 65–70% weight savings when substituting steel designs.

Versatile

Lightweight magnesium alloys can be shaped into plate by rolling and extruded into both solid and hollow profiles. These can be further shaped using forging, pressing, bending or simply machining from solid.

Highly machinable

Magnesium alloys are the easiest of all structural metals to machine.

Advantages include:

• Low power consumption (45% less than aluminium)
• Fast machining rate (55%)
• Excellent surface finish
• Reduced tool wear
• Well broken chips

High strength

Alloys are available that have comparable properties with other structural metals – with the added advantage of superior performance at elevated temperatures (good creep resistance and tensile strength).

EMI/RFI shielding

Has inherent screening properties, useful for electronic enclosures and has good thermal conductivity for heat dissipation.

Vibration damping

Magnesium alloys have excellent vibration damping properties.

Corrosion resistance

Modern alloys have good corrosion resistance. For more severe environments, there are a range of surface passivation and top coat treatments commercially available.

We’d love to hear about your applications, why not get in touch with us today to discuss how we can help increase the performance of your design?