Company insight
Custom-made medical alloys at a small scale
Innovation is a valuable commodity in an industry always on the hunt for new materials. As medical devices become smaller and more precise in their function, ideas that drive miniatursation are the most highly prized of all. Gary Davies, production and business unit manager medical and Thomas Helander, R&D expert at Sandvik Materials Technology, tell Jim Banks how Sandvik uses it’s 160 year’s knowledge to develop new advanced medical alloys.
nd-users want medical devices that allow them to return to normal life as quickly as possible, and miniaturisation is a key factor in reducing post-operative trauma and healing times. The less intrusive a device is, the shorter the recovery time.
E
This is the thinking that has driven the development of EXERA precision medical wire and wire-based components at engineering group Sandvik, opening up new avenues of wire configuration developments. “The industry has been working towards minimally invasive devices and ways to provide therapy that do not require long recovery times in the hospital,” says Gary Davies, production and business unit manager medical.
Glucose monitoring is one application that EXERA wires are used in. Others are used in devices investigating blockages in the cardiovascular system or delivering therapies directly into the nervous system, such as electrical stimulation of the brain. “Because they go into the body through the carotid or femoral artery, or into the central nervous system, the wires have to be small – 15–20µm in diameter – and you need the right custom melts to provide alloys with specific properties,” Davies explains.
Big challenges at the small scale Choosing the right alloy for a specific application is crucial. One may be more sensitive to changes in temperature or pressure, another may be better suited to delivering a precise electrical stimulus, and a third might be for its magnetic properties. Assessing these properties and performing small-scale custom melts to deliver the ultra- fine wire is the job of Thomas Helander, one of the R&D experts at Sandvik, and his team of materials scientists. He draws on vast experience within the company, which is
Sandvik can offer custom melt at the 1kg scale, which speeds up the go-to-market process and reduces waste.
best known for providing innovative materials to demanding industries, such as aerospace and energy.
“Melts are usually done on a large scale – 50–100t – but that would be very wasteful for these applications,” Helander explains. “The company makes many alloys for other industries, so we can use the expertise to prove the concept, model [it] and set up a custom melt at the 1kg scale, which brings its own challenges.”
At the smaller scale, it can be hard to control the chemical composition of an alloy and reduce the level of impurities, and processing alloys into ultra-fine wire requires a high level of precision.
“It was a long process to develop small- scale processes, especially as we are using a huge variety of alloys,” remarks Helander. “We are still learning every day, but that is just part of what we do in R&D. Some special alloys in the medical device industry can be highly reactive and for others, hot working must be done within a very narrow temperature range, as with cobalt and
Medical Device Developments /
www.nsmedicaldevices.com
titanium, which are commonly used to improve biocompatibility.”
Furthermore, some alloys contain highly reactive elements that can only be added to the melt at the very last moment. “Few companies have the complete control over the supply chain that we have from the melt through to delivery, to the device manufacturer,” says Davies. “That is why we are able to keep pace with the development processes in the medical device sector.”
An essential webinar
At the end of April 2021, senior medical wire-based components designers and R&D metallurgy experts at Sandvik presented a webinar that is still available to view online, explaining the evolution of EXERA medical wire and wire-based components. It could prove to be essential for design engineers and device manufacturers as they hatch ideas for the next generation of devices. ●
https://exera.sandvik 91
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133
