DE723345C - Process to avoid surface cracks in metallic components surface-treated by diffusion - Google Patents
Process to avoid surface cracks in metallic components surface-treated by diffusionInfo
- Publication number
- DE723345C DE723345C DEB184449D DEB0184449D DE723345C DE 723345 C DE723345 C DE 723345C DE B184449 D DEB184449 D DE B184449D DE B0184449 D DEB0184449 D DE B0184449D DE 723345 C DE723345 C DE 723345C
- Authority
- DE
- Germany
- Prior art keywords
- diffusion
- treated
- metallic components
- cracks
- avoid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
- Heat Treatment Of Articles (AREA)
Description
Verfahren zur Vermeidung von Oberflächenrissen in durch Diffusion oberflächenbehandelten metallischen Bauteilen Die Erfindung bezieht sich auf Verfahren-zur Vermeidung von Oberflächenrissen üi durch Diffusion oberflächenbebandelten metallischen Bauteilen, insbesondere solchen, die durch ein Nitrierverfahren behandelt werden, von d,'em in den folgenden Ausführungen ausgegangen g werden 'oll. s Die Nitrierschicht ist wesentlich spröder als der.Kernwerkstoff, so daß bei hohen Beanspruchungen, in Ab- bröckeln oder Einreißen der Nitrierschicht beobachtet wird. Diese Erscheinung tritt besonders an solcherf Stellen auf, an denen mit örtlich sehr hohen Spannungsspitzen gerechnet werden muß. Die Verhältnisse seien an Hand des Beispiels einer Schraube erläutert, die zur Erzielung einer groäen. Verspannkraft über die Proportionalitätsgrenze hinaus unter Umständen bis an die Streckgrenze des Werkstoffes angezogen wird. Infolge der hohen Flächenpressungen neigen solche Schrauben zum Fressen in den Gewindegängen, eine Erscheinung, die besonders dann sehr störend ist, wenn die»Schraube häufig-er gelöst werden muß. Man versucht, dem Fressen durch eine Oberflächenbehandlung entgegenzuwirken, insbesondere. durch das Nitrieren des Bolzeng,ewinde#. Wenn auch hierdurch das gewünschte Ergebnis erzielt wird, so treten doch auf der anderen Seite im Gewindegrund, teilweise sogar im Schaft, Risse in der Nitriexschicht auf, und zwar, wie bereits gesagt, wegen der Sprödigkeit der Nitrierschicht, die der sehr weitgehenden Verformung des Kernwerkstoffes nicht folgen kann.Method for avoiding surface cracks in metal components surface-treated by diffusion will be 'oll. s The nitriding layer is much more brittle than der.Kernwerkstoff so that crumble or high stresses in the absence tearing of the nitriding layer is observed. This phenomenon occurs particularly in those places where very high local voltage peaks are to be expected. The relationships are explained using the example of a screw that is used to achieve a large. Bracing force beyond the proportionality limit may be tightened up to the yield point of the material. As a result of the high surface pressure, such screws tend to seize in the threads, a phenomenon which is particularly annoying when the screw has to be loosened frequently. One tries to counteract the seizure by means of a surface treatment, in particular. by nitriding the bolt thread #. Even if the desired result is achieved in this way, on the other hand, cracks in the nitriex layer occur on the other side in the thread root, sometimes even in the shaft, and indeed, as already mentioned, due to the brittleness of the nitride layer and the very extensive deformation of the core material can not follow.
Um derartigen schädlichen Erscheinungen an metallischen Bauteilen, die einer Oberflächenbelandlung durch Difftision unterzogen wer-den, vohubeugen, wird gelnäß der Erfindung vorgeschlagen, den Bauteil w»-rend dieser Oberflächenbehandlung einer Beanspruchung zu unterwerfen, die der betriebsmäßig auftretenden Beanspruchung artgleich ist. Die Höhe der Beanspruchung wird vort Fall zu Fall festgelegt werden müssen. Der wünschenswerte Fall ist der, daß die Beanspruchung während des Vorganges der Oberflächenbehandlung gleich der betriebsmäßigen Beanspruchung ist. Das wird sich. aber praktisch nicht- immer verwirklichen lassen. In solchen Fällen wird man dann gemvungen sein, mit der Beanspruchung unterhalb derbetriebsmäßig-en Werte zu bleiben. Man erreielit dabei naturgemäß trotzdem eine Verbesserung gegenüber der spannungslosen Oberflächenbehandlung. Andererseits sind Fälle denkbar, in denen es zweciLtnäßig ist, die Beanspruchung des Bauteils während der Oberflächenbehandlung über den betriebsmäßig auftretenden höchsten Wert zu steigern.To prevent such harmful phenomena on metallic components, which are subjected to a surface treatment by diffusion, prevent, it is proposed according to the invention, the component during this surface treatment subject to a load that corresponds to the operationally occurring load is of the same kind. The amount of stress will be determined on a case-by-case basis have to. The desirable case is that the stress occurs during the process the surface treatment is equal to the operational stress. That will themselves. but practical not always be realized. In such Cases you will then be tempted to deal with the stress below the operational level Values to stay. Naturally, an improvement over this is achieved in spite of this the tension-free surface treatment. On the other hand, cases are conceivable in which it is expedient to reduce the stress on the component during the surface treatment to increase above the operationally occurring highest value.
Claims (1)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DEB184449D DE723345C (en) | 1938-08-28 | 1938-08-28 | Process to avoid surface cracks in metallic components surface-treated by diffusion |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DEB184449D DE723345C (en) | 1938-08-28 | 1938-08-28 | Process to avoid surface cracks in metallic components surface-treated by diffusion |
Publications (1)
Publication Number | Publication Date |
---|---|
DE723345C true DE723345C (en) | 1942-08-04 |
Family
ID=7009796
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DEB184449D Expired DE723345C (en) | 1938-08-28 | 1938-08-28 | Process to avoid surface cracks in metallic components surface-treated by diffusion |
Country Status (1)
Country | Link |
---|---|
DE (1) | DE723345C (en) |
-
1938
- 1938-08-28 DE DEB184449D patent/DE723345C/en not_active Expired
Similar Documents
Publication | Publication Date | Title |
---|---|---|
DE1157175B (en) | Safety head piece for lifting collars and drill rods | |
EP1455101A1 (en) | Screw and process for making a screw with a protective coating | |
DE723345C (en) | Process to avoid surface cracks in metallic components surface-treated by diffusion | |
DE102011001176A1 (en) | threaded sleeve | |
DE707777C (en) | Screw nut | |
AT156457B (en) | Entry screw connection for cables, damp-proof lines, etc. like | |
DE896037C (en) | Method of manufacturing fastening screws | |
DE946043C (en) | Pipe for deep drilling purposes | |
DE579564C (en) | Method and device for the production of screw connections made of rustproof metal in wooden goods, especially in handle fastenings for scrubbers u. like | |
EP0077952A1 (en) | Method for the frictional connection of reinforcement steels concrete construction | |
DE884819C (en) | Contact wire butt clamp, especially for profiled contact wires | |
DE161092C (en) | ||
DE598169C (en) | Method of securing a propeller wing in a hub or metal sleeve | |
DE615860C (en) | Multi-part button, especially trouser button | |
DE662198C (en) | Device for securing the tight fit of screw bolts in wooden panels or the like. | |
DE446252C (en) | Clamping device for wires and similar pulling elements | |
AT152747B (en) | Fixing of overhead line insulators on their supports. | |
DE887264C (en) | Process for pressing inserts with female threads into synthetic resin pressed parts | |
DE479736C (en) | Process for the production of a connecting terminal for electrical lines with captive parts | |
DE657797C (en) | Partial chain tree for round and flat chain knitting machines | |
DE914571C (en) | Process for avoiding seizure of screw connections that are stressed at higher temperatures | |
DE2508962B1 (en) | Hot-dip galvanized threaded bolt | |
DE575080C (en) | Screw bolts for slide connections | |
DE403965C (en) | D-handle for shovels, spades, forks with a retractable core in the handle | |
DE579097C (en) | Procedure for attaching anchor points to ropes |