Protolabs Insights: Eloxieren - Schutz und Veredelung Ihres Aluminium-Teils
Text im Video
00:00[Music]
00:07welcome to the master class this week we
00:10are taking a closer look at anodizing
00:12aluminium parts and why it is a great
00:15way to protect this metal or to add a
00:18decorative finish so let's start with a
00:21really cool fact aluminium oxide is the
00:24second hardest substance known to man
00:26only a diamond dis harder I'll give you
00:29a second to let that sink in this means
00:32that anodizing can protect your part
00:34against abrasion and also corrosion it's
00:37also good to look at and can be dyed so
00:41you may offer it purely for aesthetic
00:43reasons in the next couple of minutes we
00:45are going to explore the process of
00:47anodizing but more importantly I will
00:49help you get what you want from it but
00:53first of all here is the science bit
00:56anodizing is an electrolytic passivation
00:59process it's called anodizing because
01:02the part to be treated forms the anode
01:04electrode of an electrical circuit the
01:07most common method is sulfuric acid
01:10anodizing the part is cleaned placed in
01:13the sulfuric acid and then a positive
01:16charge is applied to it and a negative
01:18charge is applied to the place
01:20there are also immersed in the acid the
01:23aluminium part combines with the
01:25negatively charged are oxygen ions to
01:28create aluminium oxide okay if science
01:32lesson is over let's move on to what you
01:35really need to know the first question
01:38that you should ask yourself is why why
01:41do you want your part
01:42anodized easy because you need to
01:45protect your part or is it because you
01:47want to achieve a decorative finish the
01:50answer to this question will affect the
01:52thickness of the coating that you need
01:54the thicker the coating
01:56the more protection your part will have
01:58now we are only talking about microns
02:02here or a millionth of a meter but as
02:05the saying goes every little bit counts
02:07for decorative finishes you will need a
02:10minimum thickness of between 5 to 15
02:13microns if you want the part died
02:16afterwards then we would recommend some
02:18leek between 15 to 25 microns of course
02:22a thicker layer will improve the parts
02:25abrasion and corrosive resistance if it
02:28needs this protection then it should
02:30have what we call a hard anodizing
02:33finish this produces a thickness of
02:36between 25 to 50 microns now let's say
02:40that you want your part anodizing how do
02:43we know that your supplier is up to
02:45scratch well here are a couple of
02:48standards for you for decorative
02:50anodizing check that the process meets
02:52iso 75 9 9 and for hard anodizing it
02:56needs to me iso100 74 ok what else do
03:01you need to think about well you
03:03remember that we talked about how your
03:05aluminium part forms part of electrical
03:07circuit well this means that it needs to
03:10have at least one electrically
03:12conductive point in the component at all
03:15times that point will get no coverage
03:18and will not be anodized now don't worry
03:21too much because we are probably talking
03:23about 0.1% of the surface on your part
03:28what it does mean is that you need to
03:30think about how your component will be
03:33mounted or jigged
03:35jigging serves two purposes it maintains
03:38the electrical contacts and it also
03:40ensures that the part does not fall off
03:42during the process and we don't want
03:45that now do it the conducting or jigging
03:48point is often a threaded hole which
03:51gives a great electrical contact it
03:54needs to be more for hard anodizing
03:57because this process needs higher
03:59voltages so your supplier and they need
04:02to tap a threaded bolt our best advice
04:05though is to work with your supplier
04:07typically the best place would be on a
04:10hidden face or a non-critical surface to
04:13hide the contact marks so anodizing is a
04:17great choice for protecting aluminium
04:19parts but as they say on the BBC other
04:22options are
04:23available to you it really comes down to
04:26your design needs and what functionality
04:29you need for instance another good
04:31option is chromate conversion coating it
04:35provides a protective film to improve
04:38corrosion resistance for your aluminium
04:40part and is a great primer for paint it
04:43also retains the metals conductivity so
04:47there you have it and the diving is a
04:49great way if you want a decorative
04:51finish or to protect your aluminium part
04:54it's not the only solution though so
04:56don't get sold on the idea if your
04:58supplier only provides this and not any
05:01other alternatives well that is it for
05:04this week I hope you found the video
05:06informative and we look forward to
05:08seeing you next time
05:11[Music]
Letzte Änderung: 15.04.2020