What are the metal plates for spinal surgery made of?

Various metals. Modern spinal plates such as those used in the cervical spine are usually made out of titanium which still allow the patient. In fact most spinal plants are made of titanium though in scoliosis some surgeons still prefer stainless rods. Some are even made of cobalt chrome.
Titanium alloy. Most of the spinal instrumentation these days, consisting mainly of rods and screws, are made of titanium alloys. However depending upon the application or surgeon preference cobalt-chrome alloys are also available.
Depends. Most spinal instrumentation used today is titanium, which allows the spine to be images using MRI postoperatively. Some implants are made of a combination of other materials known as alloys, the most common of which is cobalt chrome. Thank you for your question.
A few options. Stainless steel is used, but less frequently these days. Titanium alloy made of titanium, vanadium and aluminum, is most common, with good imaging characteristics in MRI and ct as compared to stainless steel. The newest alloy used in spinal implants is cobalt chrome, which allows the use of thinner rods, but has imaging characteristics closer to titanium than to stainless steel.