NC258

SAC305

Lead-Free No Clean Solder Paste

Features:

- Long Pause-to-Print Capabilities

- Enhances Fine Print Definitions

- No Head-in-Pillow

- Excellent Wetting, Even Leadless Devices

- Reduced Voiding

- RoHS Compliant

Description:

NC258 has been developed to offer long pause-to-print capabilities while enhancing fine print definitions. NC258 reduces

such defects as voiding and eliminates head-in-pillow. The superior wetting ability of NC258 results in bright, smooth and

shiny solder joints. It also offers very low post process residues, which remain crystal clear even at the elevated

temperatures required for today’s lead-free alloys.

Printing:

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Apply sufficient paste to the stencil to allow a smooth, even roll during the print cycle (a bead diameter of 12 to 16

mm (½ to ⅝ inch) is normally sufficient to begin).

-

Apply small amounts of fresh solder paste to the stencil at controlled intervals to maintain paste chemistry and

workable properties.

-

NC258 provides the necessary tack time and force for today’s high speed placement equipment, which will enhance

product performance and reliability.

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Cleaning of your stencil will vary by application; however, it can be accomplished using AIM DJAW-10 stencil

cleaner.

RECOMMENDED INITIAL PRINTER SETTINGS BELOW ARE DEPENDENT ON PCB AND PAD DESIGN

PARAMETER

RECOMMENDED INITIAL SETTINGS

PARAMETER

RECOMMENDED INITIAL SETTINGS

Squeegee Pressure

0.9 - 1.5 lbs/inch of blade

PCB Separation Distance

0.75-2.0 mm (.030-.080”)

Squeegee Speed

0.5 - 6 inches/second

PCB Separation Speed

0.5 - 2 mm/second

Snap-off Distance

On Contact 0.00 mm (0.00”)

Reflow Profile:

Two unique profile families are depicted below; both can be used in ramp-spike or ramp-soak-spike applications,

and they each have similar reflow temperatures. The two profiles differ in where they reach their respective peak

temperatures, as well as the time above liquidus (TAL). The shorter profile of the two would apply to smaller

assemblies, where as the longer profile would apply to larger assemblies, such as backplanes or high-density

boards. The shaded area defines the process window. Oven efficiency, board size/mass, component type and

density all influence the final profile for a given assembly. These profiles are starting points, and processing

boards with thermal-couples attached is recommended to optimize the process.