Changes

==Stamped Contact Parts==Stamped electrical contact parts typically consist of a base carrier material towhich a contact material is attached by various methods ''(Fig. 3.17)''<figure id="fig:Plated_and_contact_containing_pre_stamped_strips_and_stamped_parts">[[File:Plated and contact containing pre-stamped strips and stamped parts. jpg|right|thumb|Figure 1: Plated and contact containing pre-stamped strips and stamped parts for different applications]]</figure>They serveas the important functional components in many switching andelectromechanical devices for a broad range of electrical and electronicapplications. On the one hand A great advantage ist that they perform the mostly loss-free electricalcurrent transfer and the closing and opening of electrical circuits. In addition , thecontact carriers are important mechanical design components , selected to meetthe requirements on electrical, thermal, mechanical , and magnetic properties.

The increasing miniaturization of electromechanical components requires eversmaller stamped parts with low dimensional tolerances. Such precisionstamped parts are needed in the automotive technology for highly reliableswitching and connector performance. In the information and data processingtechnology they transfer signals and control impulses with high reliability andserve as the interface between electronic and electrical components. Fig. 3.17:Plated and contactcontaining pre-stamped strips andstamped parts for differentapplications

Stamped parts are produced as single pieces, in pre-stamped strip and combconfigurations. Depending on the requirements and application the contact andbase material as well as the coating and attachment technology is carefullyselected. *Coated stamped partsStamped parts can be selectively or completely coated with precious metalcontaining materials based on gold, palladium, and silver as well asnon-precious materials such as tin, nickel and copper ''(Fig. 3.17)''. For stampedparts in high volumes like those used as electrical components in automobilesthe carrier material is mostly coated in a reel-to-reel process starting with eithersolid or pre-stamped strips (see also chapter 7.1.1.3). Frequently the prestampedstrip will be used directly in further automated assembly of the finishedfunctional component. As an alternative finished stamped parts can beelectroplated using barrel and rack plating methods. Very thin coating layers with tight tolerances are deposited by electroplating. Formany applications the high mechanical wear resistance is advantageous. Sinceeven very thin layers are mostly pore-free, these coatings also act as aneffective corrosion inhibitor. The type of coatings, the sequence of multiplelayers, and the coating thickness, for example for connectors, are chosenaccording to the requirements for the end application. *Clad stamped parts

For many applications thicker *'''Coated stamped parts'''Stamped parts can be selectively or completely coated with precious metal surfaces or AlSi layers arenecessary. These cannot be deposited by electroplating. Besides meltmetallurgicallyproduced , containing materials based on the basis of gold, palladium , and silver,as well asalso powdernon-metallurgical precious materials are required frequentlysuch as tin, nickel and copper. The metallurgicalbond between these contact materials and For stamped parts in high volumes like those used as electrical components in automobiles, the carrier material is mostly copper based substratesis achieved through various mechanical cladding methods coated in a reel-to-reel process, starting with either solid or pre-stamped strips (see also chapter3.2.1[[Electroplating (or Galvanic Deposition)#Electroplating of Semi-finished Materials| Electroplating of Semi-finished Materials]]). In this way also aluminum clad strips are manufactured in which Frequently thealuminum layer serves as the bondable surface prestamped strip will be used directly in further automated assembly of the interface betweenelectromechanical connections and electronic circuitsfinished functional component (<xr id="fig:Plated_and_contact_containing_pre_stamped_strips_and_stamped_parts"/>). These clad semifinishedmaterials can be further fabricated into pre-stamped strips, in combformAs an alternative, or single finished stamped parts ''(Fig. 3.18)''can be electroplated using barrel and rack plating methods.

[[File:Examples of clad stamped parts.jpg|right|thumb|Examples of clad stamped parts]]Fig. 3.18:Examples of clad *'''Clad stamped parts'''

*Welded For many applications, thicker precious metal surfaces or AlSi layers are necessary. These cannot be deposited by electroplating. Besides meltmetallurgically produced materials on the basis of gold, palladium and silver, also powder-metallurgical materials are required frequently. The metallurgical bond between these contact materials and the mostly copper based substrates is achieved through various mechanical cladding methods (see also chapter [[Manufacturing of Semi-Finished Materials#Clad Semi-Finished Pre-Materials (Contact-Bimetals)| Clad Semi-Finished Pre-Materials (Contact-Bimetals)]]). In this way, also aluminum clad strips are manufactured in which the aluminum layer serves as the bondable surface in the interface between electromechanical connections and electronic circuits. These clad semifinished materials can be further fabricated into pre-stamped strips, in comb form or single stamped parts (<xr id="fig:Examples of clad stamped parts"/><!--(Fig. 3.18)-->).

Welded <figure id="fig:Examples of clad stamped parts can be fabricated by various methods (see also Chapter">3.3.3). Single contact pieces can be attached to pre-[[File:Examples of clad stamped or finishedstamped strips as weld buttons and wire or profile segments by electricalresistance welding. Contact parts can also be stamped from seam-weldedsemi-finished strip. Fitting the end application contact materials based on gold,palladium and silver. Depending on the contact material and the design jpg|right|thumb|Figure 2: Examples of thefinished contact component the contact bottom surface may be consist of aclad stamped parts]]weldable backing material.</figure>

*Brazed '''Welded stamped parts'''

Brazed Welded stamped contact assemblies are manufactured parts can be fabricated by two joining various methods(see also chapter 3.3.2[[Attachment of Single Contact Parts#Welding Processes| Welding Processes]]). The Single contact material is either pieces can be attached by resistanceto pre-stamped or induction brazing to base metal carriers finished stamped strips as prefabricated contact tip weld buttons and wire or theyare profile segments by electrical resistance welding. Contact parts can also be stamped from brazed seam-welded, semi-finished toplay strip. It is typical for brazedFitting the end application contact parts that materials based on gold, palladium and silver. Depending on the contact material consists and the design of silver based the finished contact component, the contact materialand bottom surface may be consist of a good conducting copper base weldable backing material with larger cross-sectional areafor the usually higher current carrying capacity.

*Stamped contact '''Brazed stamped parts with rivets'''

Riveted Brazed stamped contact parts assemblies are manufactured with the use of contact rivetswhich are transferred over suitable feed mechanisms correctly oriented intoholes punched into the carrier ''(Fig. 3.19)''. Frequently also wire or wire segmentsresp. are used which are subsequently coined and formed into the desiredcontact shape by two joining methods (see also chapter 3.3.1[[Attachment of Single Contact Parts#Brazing Processes| Brazing Processes]]). Both attachment methods have theirdistinct advantages. Using composite The contact material is either attached by resistance or induction brazing to base metal carriers as prefabricated contact tip or trithey are stamped from brazed semi-metal rivets allows limiting finished toplay strip. It is typical for brazed contact parts that the usecontact material consists of precious metal custom tailored to the volume needed silver based contact material and a good conducting copper base material with larger cross-sectional area for specific switchingrequirements. For wire staking the precious metal usage is usually higher butthe staking can be performed at significantly higher production ratesand the additional rivet making step is eliminatedcurrent carrying capacity.

Fig. 3.19:Examples of riveted stamped *'''Stamped contact partswith rivets'''

*PreRiveted stamped contact parts are manufactured with the use of contact rivets, which are transferred over suitable feed mechanisms correctly oriented into holes punched into the carrier (<xr id="fig:Examples of riveted stamped parts"/><!--(Fig. 3.19)--mounted component >). Frequently; also wire or wire segments resp. are used which are subsequently coined and formed into the desired contact shape (see also chapter [[Attachment of Single Contact Parts#Mechanical Attachment Processes| Mechanical Attachment Processes]]). Both attachment methods have their distinct advantages. Using composite or tri-metal rivets allows limiting the use of precious metal custom tailored to the volume needed for specific switching requirements. For wire staking, the precious metal usage is usually higher but the staking can be performed at significantly higher production rates and the additional rivet making step is eliminated.<figure id="fig:Examples of riveted stamped parts">[[File:Examples of riveted stamped parts.jpg|right|thumb|Figure 3: Examples of riveted stamped parts]]</figure>

Components *'''Pre-mounted component stamped parts consist of a minimum of two carrier parts whichdiffer in their material composition and geometrical form and the contactmaterial''(Fig. 3.21)''. The assembly of these components as single pieces or stampingprogressions is performed in a stamping die by riveting or coining. To increasethe current carrying capacity at the joining area an additional welding step canbe added. Depending on the requirements the different properties of the twocarrier components can be combined. As an example: the high electricalconductivity of a contact carrier blade is joined with the thermal or mechanicalspring properties of a second material to form a functional component. For thisprocess both carrier base materials can also be coated with additionallayers of other functional materials.

Components stamped parts consist of a minimum of two carrier parts which differ in their material composition and geometrical form and the contactmaterial (<xr id="fig:Examples of pre-mounted stamped component parts"/><!--(Fig. 3.20?)-->). The assembly of these components as single pieces or stamping progressions is performed in a stamping die by riveting or coining. To increase the current carrying capacity at the joining area, an additional welding step can be added. Depending on the requirements, the different properties of the two carrier components can be combined. As an example:the high electrical conductivity of a contact carrier blade is joined with the thermal or mechanical spring properties of a second material to form a functional component. For this process, both carrier base materials can also be coated with additional layers of other functional materials.<figure id="fig:Examples of pre-mounted stampedcomponent parts">[[File:Examples of pre-mounted stamped component parts.jpg|right|thumb|Figure 4: Examples of pre-mounted stamped component parts]]</figure>

Stamped parts which are insert molded into or combined with plastic parts areused in electromechanical components (see Chapter 10[[Electromechanical Components | Electromechanical Components ]]).

Modern stamping tools usually employ a modular design with integrateddimensional and functional controls ''(<xr id="fig:Progressive die for stamped contact parts"/><!--(Fig. 3.21)''-->). <figure id="fig:Progressive die for stamped contact parts">[[File:Progressive die for stamped contact parts.jpg|right|thumb|Figure 5: Progressive die for stamped contact parts]]</figure>Depending on the part and volume requirementson the parts and the volumes , they are built with steel or carbide (-steel) insertswhich that are also coated with a wear -resistant material such as for example TiN forlonger life.

A special stamping process is precision stamping for contact parts , made fromthin strip materials with thicknesses in the range of 0.05 – 2.5 mm. With the highcapacity stamping technology , up to 1400 strokes/min can be reached for highvolume parts. During the actual stamping operation , frequently other processessuch as thread-forming, welding of contact segments and insertion and formingof contacts from wire segments are integrated. Depending on the productionvolumes volume, these operations can also be performed in multiplesseveral times.

The quality of the tools used for stamping, like progressive dies and stamp-formingtools is important for the final precision and consistency of the parts. During highspeed stamping the tools are exposed to extreme mechanical stresses which mustbe compensated for , to ensure the highest precision over long production runs. Withsuch high quality , progressive dies parts of high precision with a cutting width of lessthan the material thickness and with strict quality requirements for the cutting surfaces, can be manufactured.To ensure the highest demands on the surface quality of precision contact parts , quiteoften vanishing oils are used as tool lubricants. Cleaning and degreasing operationscan also be integrated into the stamping process. Additionally , most stamping linesare also equipped with test stations for a 100% dimensional and surface qualitycontrol.During the design of stamping tools for electrical contacts , minimizing of processscrap and the possibility to separate the precious metal containing scrap must beconsidered. Fig. 3.21:Progressive die for stamped contact parts[[Category:Manufacturing Technologies for Contact Parts|Category]]