PREFORMS

Soldering preforms

Soldering preforms : tin-based alloy parts for specific applications

Preforms are tin-based alloy parts that are made to measure for specific applications. They can take the form of squares, rectangles, washers, collars, rings or sleeves. They may also feature an internal or external flux whose activation depends on the application. They enable the creation of soldered joints where the quantity of the alloy is perfectly measured. They are used in areas such as semi-conductors, aeronautics, the automotive industry and electronic and mechanic assemblies. They complement the METACONCEPT Group’s tin-based cream or tin-silver cream and solid or cored wire. Waste originating from the use of these products can be recycled.Contact our recycling department to find out more. Preforms are used as part of manual or fully automated processes.
Have you defined the type of application ? Contact us. Our technical staff will be happy to assist you in choosing the most suitable preform.

Characteristics of preforms

The table below shows the most commonly used alloys in soft soldering with different types of flux.

ALLOYS

EN 29453 classification
Density g/cm3
Solidus – Liquidus
Comments
Packaging
Sn5 – Ag2 – Pb93
11,13
296°C – 301°C
N/A
Bulk
Sn40 – Pb60
9,72
183°C – 235°C
N/A
Bulk
Sn50 – Pb50
9,32
183°C – 215°C
N/A
Bulk
Sn60 – Pb40
8,91
183°C – 190°C
N/A
Bulk
Sn62 – Pb36 – Ag2
8,81
178°C
N/A
Bulk
Sn63 – Pb37
8,79
183°C
N/A
Bulk
Sn48 – In52
7,29
118°C
Lead-free alloy*
Bulk
Sn96 – Ag4
7,39
221°C
Lead-free alloy*
Bulk
SAC 305
7,38
217°C – 219°C
Lead-free alloy*
Bulk
SAC 307
7,39
217°C – 228°C
Lead-free alloy*
Bulk
Sn97 – Cu3
7,33
230°C – 250°C
Lead-free alloy*
Bulk
Sn99 – Cu1
7,3
230°C – 240°C
Lead-free alloy*
Bulk
Sn100
7,28
232°C
Lead-free alloy*
Bulk

(*) Lead-free alloys – European standard no. 2000 / 53 / CE
The METACONCEPT Group can look into creating any type of alloy upon request. Alloys: tin-indium, tin-bismuth, low melting temperature alloy. Please do not hesitate to contact us.

FLUX

Type
Nature
JSTD-004 Classification
Acidity level (mg KOH/g)
Halogen rate
Residue removal
MRS2
Resin
ROM1
175
1,3
Clean with a solvent
MRS7
Resin
ROM1
220
1
Clean with a solvent
MSP7
Organic
ROM1
130
1,1
Clean with a solvent
MSP15
Resin
ROLO
386
0
Clean with a solvent

Comments: Always use an appropriate flux.Contact our technical department to ascertain which product is most suited to your application.

When the process allows, the advantages of using preforms are as follows:

Advantages
Results
Exact quantity of alloy applied
Improves the quality and the finish; saves alloy
Machineable
Reduces costs and non-compliance
Flush joints
Simplifies the assembly process
High % of correct joints
Reduces quality tests
Available in a pre-fluxed version
Eliminates the need for an external flux
Measurement of the % of the flux
Reduces residues after brazing

Applications

Preforms can be used in all brazing applications where the quantity of alloy must be very closely controlled. Preforms may also be used to create tin-based fusible parts with a low melting temperature.

Fields of application

  • Automotive industry
  • Heat exchangers
  • Aeronautics
  • Spatial
  • Connectivity
  • Semi-conductors
  • Fire safety
  • Various electronic and mechanical assemblies

Implementation

The product safety information sheet below is available upon request from the METACONCEPT Group.

The effective use of preforms demands a rigorous and faithful implementation. Contact the METACONCEPT Group’s technical department who, after selection of the alloy and its form, will provide the appropriate implementation sheet.

Precautions of use

To prevent burns caused by the molten metal, it is advisable to wear a protective apron, shoes, gloves, helmet and glasses.
– Do not smoke at the workstation.
– The workstation must be well ventilated.
– Wash your hands when leaving the workstation.

Comments :
Always use a flux suited to the intended use. Contact our technical department to ascertain which product is most suited to your application.

All of the information contained in this document is provided for informational purposes only and the METACONCEPT Group will not be held liable for it.