Protolabs Insights: Eloxieren - Schutz und Veredelung Ihres Aluminium-Teils

Wir werfen einen näheren Blick auf das Eloxieren von Teilen aus Aluminium und erfahren, warum es sich super eignet, um dieses Metall zu schützen oder ein dekoratives Oberflächenfinish hinzuzufügen.

Text im Video


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


Letzte Änderung: 15.04.2020