Tag Archives: failures

Racing to Failure?

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Reuters is reporting that Samsung has temporarily suspended production of the Galaxy Note 7 smartphone after replacements for the first batch of devices also proved to be almost as good at spontaneously combusting as they are at surfing the Web.

One brand manager went so far as to compare the self-igniting smartphones to the Ford Pinto, whose rear-end fuel tanks had the unfortunate tendency to explode upon contact.

Samsung’s situation isn’t unique: Apple experienced similar problems with previous iterations of the iPhone. But given the speed with which new phone models are brought to market, one begins to wonder whether these defects are part of a larger failure of the process itself.

Is is possible we’ve reached an inflection point whereby, in the rush to get product to market, the validation phase is — pardon the pun — being short-circuited? Are suppliers properly vetted, product thoroughly tested, risks appropriately balanced?

Or has consumer electronics reached a point where it’s a race not to market but to failure?

Oct. 11 addendum: The Korea Herald and others are now reporting Samsung has decided to pull the plug completely on the Note 7. The estimated cost: Billions.

 

 

Questions on Tin Whiskers

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Folks,

In a recent post, I shared my perspective on the pluses, minuses and neutral aspects of lead-free solder assembly. In the minus category, I listed tin whiskers. A few people commented that tin whiskers were the biggest concern in lead-free assembly. I have trouble understanding this perspective. I’m not saying these folks are wrong, just that I don’t understand their viewpoint.

First, let me say that I appreciate the concern for tin whiskers in mission critical electronics such as military, aerospace and medical. I am also sympathetic to the fact that, even though these types of electronics are exempt from RoHS, they may have to use RoHS compliant products because non-RoHS compliant products may not be available.

When I discuss the topic of tin whiskers, people will point me to NASA’s tin whisker failures website . However, when one goes to the site, there are only about twenty tin whisker fails referenced, many due to bright tin plate. Bright tin plate should never be used in mission critical electronics as it is virtually assured of producing tin whiskers. In addition, many of the articles referenced do not talk about tin whisker fails. Few if any fails are discussed relevant to RoHS (i.e. almost all fails discussed are prior to July 2006.)

I do not want to minimize the significance of tin whisker fails, some of them cost 100s of millions of dollars (e.g., satellite failures). In addition, there have been a few papers that have discussed the formation of tin whiskers even if mitigation techniques are used. Tin whiskers clearly can cause problems, but do not appear to be common, especially if mitigation techniques are used.

So here is my question, who knows of any verified tin whisker fails when tin whisker mitigation techniques were used? Tin whisker mitigation techniques typically use 2% bismuth or antimony in the tin, assure that the tin has a matte finish and use a nickel strike plating between the copper and the tin to minimize copper diffusion into the tin.

Surely if tin whiskers are a major concern, there should be many fails in the over $3 trillion worth of RoHS compliant electronics manufactured since July 2006.

Cheers,

Dr. Ron