ALPHA SLS65H免清洗助焊剂

Alpha’s Lonco SLS 65H was specifically developed to eliminate the tendency for solder balling and solder bridging-two defects which are normally associated with the use of the chip wave. Of all low solids (< 4% solids), no-clean fluxes,Lonco SLS 65H exhibits the lowest tendency for solder ball generation over a wide variety of solder masks. Lonco SLS65H should be considered for use by any assembler who has board designs which are sensitive to solder bridging,

performs pin testing, and whose specification requires an extremely low frequency of solder balls.  

GENERAL DESCRIPTION

Alpha’s Lonco SLS 65H is an active, low solids, no-clean flux. It is formulated with a proprietary mixture of organic activators.Several proprietary additives are formulated into Lonco SLS 65H which act to reduce the surface tension between the soldermask and the solder; thereby, dramatically reducing the tendency of solder ball generation. The formulation of Lonco SLS 65H is also designed to be more thermally stable; thereby, reducing the urrence of solder bridging.

FEATURES & BENEFITS

· Thermally stable activators provide the lowest solder bridging in a low solids, no-clean flux.

· Reduces the surface tension between solder mask and solder to provide the lowest solder ball frequency of any low solids,no-clean flux.

· Very low level of non-tacky residue to reduce interference with pin testing and exhibit no visible residue.

· Cleaning is not required which reduces operating costs.

· Bellcore Compliant for long term electrical reliability.

APPLICATION GUIDELINES

PREPARATION - In order to maintain consistent soldering performance and electrical reliability, it is important to begin the process with circuit boards and components that meet established requirements for solderability and ionic cleanliness. It is suggested that assemblers establish specifications on these items with their suppliers and that suppliers provide Certificates of Analysis with shipments and/or assemblers perform ing inspection. A common specification for the ionic cleanliness of ing boards and components is 5mg/in2 maximum, as measured by an Omegameter with heated solution. Care should be taken in handling the circuit boards throughout the process. Boards should always be held at the edges. The

use of clean, lint-free gloves is also mended. When switching from one flux to another, the use of a new foam stone is mended (for foam fluxing).

Conveyors, fingers and pallets should be cleaned. Bioact SC-10 Solvent Cleaner has been found to be very useful for these cleaning applications.   When foam fluxing, do not use hot fixtures or pallets. Hot fixtures/pallets will deteriorate the foam head.

FLUX APPLICATION - Lonco SLS 65H is formulated to be applied by foam, wave or spray methods. When foam fluxing, the foam fluxer should be supplied with compressed air which is free of oil and water. Keep the flux tank full at all times. The flux level should be maintained 1 inch to 1-½inches above the top of the stone. Adjust the air pressure to produce the optimum foam

height with a fine, uniform foam head. A uniform coating of flux is essential to essful soldering. When using the foam or wave method of application, an air knife is mended after the fluxing operation. An air knife will help ensure that the flux is uniformly distributed across the board and will remove the excess flux. When spray fluxing, the uniformity of the coating can be visually checked by running a piece of cardboard over the spray fluxer or by processing a board-sized piece of tempered glass through the spray and then through the

preheat section.