Nonconforming Imported Titanium

Ti: what can slip by undetected*En Español*

Some of my colleagues have already learned of this from my biomaterials presentations at APP 2010 and BMXnet conferences. This reflects upon imported jewelry, and the situations that can arise when quality controls are not normalized.

(Active Materials Laboratory)

In the spring of 2009, a device manufacturer observed difficulties when attempting to process specific lots of a titanium alloy (Ti64) that is widely used in medical devices. These difficulties were attributed to microstructural anomalies present in the material that did not conform to the material specification. The impacted lots of material were all traced to Dalian Sunny Mill in China. In response to this information, a CDRH-wide team was assembled, led by the Office of Compliance, to assess the scope and potential ramifications of the affected material. Team members included OSEL engineers from both the Division of Solid and Fluid Mechanics and Division of Chemistry and Materials Science.

Based on their expertise and assessment of available data, the OSEL engineers helped draft a letter that was distributed to device manufacturers in September 2009 to inform them of the problem and offered guidance as to identifying any nonconformities in their material. The letter also outlined additional material evaluations that would assist the Center in identifying the potential risk to patients if nonconforming material was used to produce a device. Further, once details about the nonconforming titanium alloy became available publicly, OSEL engineers collaborated with the relevant stakeholders in the ASTM International metallurgical materials subcommittee to assess the cause. The consensus is that the root cause of the nonconforming material was due to lack of adequate process control during the melting of the alloy and that this is something that cannot realistically be evaluated by inspecting the material after it is produced; rather it needs to be addressed through the melter’s Quality Systems and process control.

Source: FDA CDRHReports/ucm220291

The Latest Defective Product from China: Titanium

September 5, 2009. By Gordon Gibb Washington, DC:

Yet another defective product issue has originated in China—and while personal injury in connection with the product has yet to be identified, the alarm bells are once again ringing over the potential for yet another defective product personal injury case. This time, the battles lines are being drawn over titanium.

The latter is a specialized alloy used in various products, including orthopedic implants used during surgery. As reported by the GMP Letter September 3, a device maker was unsuccessful in processing titanium through a machine used to manufacture a device (the specific device was not identified). The manufacturer approached its supplier, G&S Titanium, an importer-distributer.

According to Roger Geiser, G&S CEO, the defect was identified as alloy segregation, an indication that the metals were not melded homogeneously. If the alloy is not melded properly, the metals remain unmixed.

G&S said the raw material was imported from Dalian Sunny Titanium Industry, an enterprise based in China. Geiser added that his company is no longer purchasing titanium from there.

While the US Food and Drug Administration (FDA) visited the G&S facility about two months ago, no details about the inspection were released. In the interim, the Orthopedic Surgical Manufacture’s Association (OSMA) is working with affected device makers to address the problem. “It’s not an easy issue,” OSMA’s Tom Craig told GMP.

Not easy because the defective titanium from China actually met international standards set out for titanium by ASTM, a standards organization. Second, nothing short of a destructive test could possibly identify the defect—although such a test would serve to weaken the titanium. Destructive tests are not required by the ASTM under current regulations.

What’s more, says Craig, the defect could be so localized that only a small piece of one device could actually be defective.

What does that mean for a patient concerned over a defective product and personal injury? Hard to say. OSMA indicated it did not know of any defective products migrating out to patients as a result of the problem. Craig also said that a few companies have initiated pre-emptive recalls, although he did not identify the manufacturers or what those products were.

G&S tested the titanium in question, which demonstrated adequate strength and chemistry specifications. “The certification we got from the supplier said this should never happen,” G&S’ Geiser said. But it did—and the defect occurred further down the supply chain than what the FDA generally inspects, said Craig. “This caught everybody off-guard.”


Continued vigilance needed for Chinese titanium

The ASTM specs for titanium have room for tightening

Roger Geiser, CEO of G&S (US distributor)

What has been done:

The ASTM F136 specification requires XRF to ASTM E539, but it did not previously until we voted on this addition in Nov. 2008.

This is a summary from ASTM F136-08 (See current revision F136)

Committee F04 has identified the location of selected changes to this standard since the last issue (F136 – 02a) that may impact the use of this standard. (Approved Nov. 1, 2008.)

(1) Section 2, Referenced Documents, was updated.
(2) Section 6 and subsections 6.1, 6.2, and 6.3 were updated.
(3) Test Methods E539, E1941, and E2371 were added to 7.2.4.

(4) Section 8.4 was deleted, and relevant information was moved to subsections 8.2 and 8.3.
(5) Mechanical Properties have been split into Table 1 for Bar, Wire, and Forgings and Table 2 for Sheet, Strip, and Plate.

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