RobbJack’s Advanced Applications Testing Facility is available to help solve your medical applications. Send us your material and we will develop a solution.

Titanium and Stainless Steel

Light, strong, corrosion-resistant and totally biocompatible, titanium is one of few materials that naturally match the requirements for implantation in the human body. Medical grade titanium alloys have a significantly higher strength to weight ratio than competing stainless steels.

Stainless steel, on the other hand, is valued for its strength and corrosion resistance to withstand repeated sterilizations and still meet ultra-high purity requirements.

Made of RobbJack’s Tuffy Grade Carbide, our XF-series end mills are engineered with a unique geometry to make tough titanium jobs easy and efficient. One aerospace customer had been going through five competitor tools to machine just one part. When they switched to RobbJack XF, they were able to machine three parts with one tool, a 1500% difference. The speeds and feeds and cubic inch removal rate of the XF series is typically five to ten times faster than traditional machining of titanium.

Cobalt Chrome

Cobalt chrome alloys are well known for their biocompatibility and offer desirable wear- and corrosion-resistance properties for implants, such as shoulder, knee and hip replacements. Cobalt chrome is also known as a difficult material to machine, particularly when milling, due to its extremely abrasive characteristics, its high hardness (especially in the 50-HRc range) and its propensity for chatter and tool heat build-up.

The RobbJack DM/MDM Die/Mold Carbide end mill offers tighter tolerances, lasts longer in difficult areas like parting lines, and produces better finishes that reduce or eliminate the need for polishing. It performs well on materials up to 70 HRc and can handle dry cutting and high temperatures. The RobbJack DM/MDM Die/Mold is made of a new carbide material and a new coating combination that lasts 450% longer than comparable carbides and coatings designed for hard metal applications—and reduces wear by 909%.

See the case study that proves it.

The TM/MTM Tuffy Grade Solid Carbide Toroid Style End Mill offers excellent precision when machining tight areas such as ribs and bores.

The HM/MHM Tuffy Grade Die/Mold End Mill excels at delivering a smooth finish on flat open areas.

Medical Plastics

For decades, medical grade plastics such as ultra-high-molecular-weight polyethylene (UHMWPE) have been used as biomaterial for use in hip, knee, and spine implants. UHMWPE has a number of characteristics that make it ideal for this purpose. It is a very tough material that is also highly resistant to most corrosive chemicals, has extremely low moisture absorption, a very low coefficient of friction, is self-lubricating, and in some forms, is 15 times more resistant to abrasion than carbon steel. It is also a demanding material for machinists, susceptible to burrs and also lines and deviations in the part.

Medical parts have to be flawless. That’s why RobbJack developed tools including the PM Series that features special geometries and polished cutting edges that produce better finishes and minimize polishing operations.

Another common medical plastic is PEEK. It is used for spinal implants because, unlike titanium or stainless steel, it is transparent in X-rays, allowing doctors to see the bone around it. PEEK can also be difficult to cut. Using the wrong tool can cause stress build-up in the part requiring added operations for stress relief—otherwise cracking or deformation may occur. Carbon-filled PEEK is extremely abrasive as well, which wears down lesser tools fast.

RobbJack’s PCD tools offer solid polycrystalline diamond that handles PEEK’s highly abrasive qualities with relative ease.