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The two most prevalent shape-memory alloys are copper-aluminium-nickel and nickel-titanium (), but SMAs can also be created by alloying zinc, copper, gold and iron.Although iron-based and copper-based SMAs, such as Fe-Mn-Si, Cu-Zn-Al and Cu-Al-Ni, are commercially available and cheaper than NiTi, NiTi-based SMAs are preferable for most applications due to their stability and practicability [1 ...
The interface dimensions for SMA connectors are listed in MIL-STD-348. [5] The SMA connector employs a 1 ⁄ 4 inch diameter, 36-thread-per-inch threaded barrel. The male is equipped with a hex nut measuring 5 ⁄ 16 inch (0.3125 inch / 7.9 mm) across opposite flats, thus taking the same wrench as a #6 SAE hex nut.
The actual welding technique utilized depends on the electrode, the composition of the workpiece, and the position of the joint being welded. The choice of electrode and welding position also determine the welding speed. Flat welds require the least operator skill, and can be done with electrodes that melt quickly but solidify slowly.
A self-expandable metallic stent (or SEMS) is a metallic tube, or stent that holds open a structure in the gastrointestinal tract to allow the passage of food, chyme, stool, or other secretions related to digestion. Surgeons insert SEMS by endoscopy, inserting a fibre optic camera—either through the mouth or colon—to reach an area of narrowing.
However, as the stent is a foreign object (not native to the body), it incites an immune response. This may cause scar tissue (cell proliferation) to rapidly grow over the stent and cause a neointimal hyperplasia. In addition, if the stent damages the artery wall there is a strong tendency for clots to form at the site.
A bare-metal stent is a stent made of thin, uncoated (bare) metal wire that has been formed into a mesh-like tube. The first stents licensed for use in cardiac arteries were bare metal – often 316L stainless steel.
If a stent has been placed as part of the PCI procedure, the patient will be given a 'medical device card' (US) with information about the implanted stent such as a medical device serial number, this is important as it informs clinicians performing future potential medical procedures, this is also the case with arterial closure systems which ...
Carotid artery stenting is an endovascular procedure where a stent is deployed within the lumen of the carotid artery to treat narrowing of the carotid artery and decrease the risk of stroke. It is used to treat narrowing of the carotid artery in high-risk patients, when carotid endarterectomy is considered too risky.