GB/T 31475-2015 Requirements for solder paste for high-quality interconnections in electronics assembly
1 Scope
This standard specifies the classification, technical requirements, test methods, inspection rules, marking, packaging, transportation and storage of the solder paste for high-quality interconnections in electronics assembly (hereinafter referred to as solder paste).
This standard is applicable to solder paste used in soft soldering when surface assembled elements and electronic circuits are interconnected.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 2040 Copper sheet
GB/T 2828.1 Sampling procedures for inspection by attributes - Part 1: Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection
GB/T 10574 (All parts) Methods for chemical analysis of tin-lead solders
GB/T 31476 Requirements for solders for high-quality interconnections in electronics assembly
GB/T 31474 Soldering fluxes for high-quality interconnections in electronics assembly
YS/T 746 (all parts) Methods for chemical analysis of lead-free tin-based solders
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
slump
phenomenon of a change in the shape of the solder paste pattern printed on a print substrate during a solder paste application test, which is a defect in solder paste
3.2
tackiness
magnitude of adhesion of solder paste to elements and the change of adhesion with the increase of time after printing of solder paste
3.3
wetting
molten solder being spread on the surface of the base metal and forming a smooth solder layer with an angle of less than 90° to the base metal
3.4
thinner
liquid preparations or pastes, with or without activators, which are added to solder pastes to regulate the viscosity and solids content of the solder paste
4 Classification and designation labeling
4.1 Classification
Solder paste can be divided into lead solder paste and lead-free solder paste according to the alloy composition. For the classification of soldering fluxes in solder paste, please refer to GB/T 31474 Soldering fluxes for high-quality interconnections in electronics assembly.
4.2 Designation labeling
The designation labeling of solder paste shall meet the following requirements:
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Classification and designation labeling
5 Requirements
6 Test methods
7 Inspection rules
8 Marking, packaging, transportation and storage
