{"id":4683,"date":"2026-08-04T11:06:56","date_gmt":"2026-08-04T09:06:56","guid":{"rendered":"https:\/\/hamco-germany.com\/?post_type=fachbegriff&p=4683"},"modified":"2026-08-06T10:52:17","modified_gmt":"2026-08-06T08:52:17","slug":"creep-behaviour","status":"publish","type":"fachbegriff","link":"https:\/\/hamco-germany.com\/en\/fachbegriff\/kriechverhalten\/","title":{"rendered":"Creeper behaviour"},"content":{"rendered":"

Terminology of plastics technology - humorous and easy to understand<\/strong><\/h2>\n

Did you know that in many cases, comparisons with nature and humans can be used to explain facts in plastics technology?<\/p>\n

Today's term: Creeper behaviour<\/strong><\/p>\n

\u201eAnyone who knows plastic chooses cement.\u201c<\/strong><\/p>\n

A professor of plastics engineering at what was then Darmstadt University of Applied Sciences is said to have once uttered this sentence. Of course, it was meant tongue-in-cheek. Because anyone who really knows plastics knows that they are fantastic materials \u2013 you just have to understand their peculiarities. And one of them is called Creep<\/strong>.<\/p>\n

What does \u2018creep\u2019 actually mean?<\/h2>\n

Imagine you sit down on a new sofa. At first, it feels wonderful. After an hour, you realise that you\u2019ve sunk in a few centimetres. This is normal for you, as it\u2019s more comfortable than sitting on a stiff board, and when you stand up, the foam seems to return to its original shape. But if that were really the case, why do sofas look worn out after a few years\u2019 use?<\/p>\n

In technical circles, this is also known as \u2018compression set\u2019. If a plastic is subjected to a load over a prolonged period, it continues to deform slowly, even though the force applied does not increase. This time-dependent deformation is known as Creep<\/strong>.<\/p>\n

Why does a plastic do that?<\/h2>\n

The difference lies within the material itself.<\/p>\n

Metals have a very rigid crystal structure. Plastics, on the other hand, consist of long molecular chains that can slowly slide past one another when under stress.<\/p>\n

Don\u2019t jerk it.
\nNot all of a sudden.
\nBut at a leisurely pace.<\/p>\n

The higher the temperature and the greater the load, the faster this happens.<\/p>\n

Why is this important?<\/h2>\n

For design engineers, creep is not a fault, but a property that must be taken into account.<\/p>\n

Under continuous load, a seal may change shape and will not return to its original position once the load is removed.<\/p>\n

A snap hook that holds perfectly today may, after prolonged use, eventually fail to \u201esnap\u201c quite as effectively.<\/p>\n

That is why, in the case of plastic components, it is not enough simply to calculate whether they today<\/strong> hold.<\/p>\n

The key question is:<\/p>\n

Will they still be around in five or ten years\u2019 time, and what can be done about it?<\/h2>\n

Design engineers have a number of options:<\/p>\n

    \n
  • select suitable materials,<\/li>\n
  • Reduce stress,<\/li>\n
  • Keep temperatures low,<\/li>\n
  • Design components to be stiffer,<\/li>\n
  • Use glass fibres or other reinforcing materials,<\/li>\n
  • or distribute loads as efficiently as possible.<\/li>\n<\/ul>\n

    After all, plastics are not bad materials \u2013 they simply require a little more long-term thinking.<\/p>\n

    Conclusion<\/h3>\n

    Creep behaviour is one of the most important properties of plastics. Anyone who ignores it may sometimes be in for some unpleasant surprises.<\/p>\n

    Anyone familiar with them can develop durable, reliable and cost-effective components.<\/p>\n

    And that brings us back to the famous quote from the professor:<\/p>\n

    \u201eAnyone who knows plastic chooses cement.\u201c<\/strong><\/p>\n

    Perhaps we should add the following today:<\/p>\n

    \u201e\u2026 or he chooses the right plastic \u2013 and designs it in such a way that any creep only occurs where it doesn\u2019t bother anyone.\u201c<\/strong><\/p>\n

     <\/p>","protected":false},"featured_media":0,"parent":0,"template":"","class_list":["post-4683","fachbegriff","type-fachbegriff","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/hamco-germany.com\/en\/wp-json\/wp\/v2\/fachbegriff\/4683","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hamco-germany.com\/en\/wp-json\/wp\/v2\/fachbegriff"}],"about":[{"href":"https:\/\/hamco-germany.com\/en\/wp-json\/wp\/v2\/types\/fachbegriff"}],"wp:attachment":[{"href":"https:\/\/hamco-germany.com\/en\/wp-json\/wp\/v2\/media?parent=4683"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}