Datasheet

Technical Data Sheet
LOCTITE
®
268
May-2004
PRODUCT DESCRIPTION
LOCTITE
®
268 provides the following product characteristics:
Technology Acrylic
Chemical Type Dimethacrylate ester
Appearance (uncured) Red, wax consistency
LMS
Appearance (form) Stick
Fluorescence Positive under UV light
LMS
Components One component - requires no mixing
Cure Anaerobic
Application Threadlocking
Strength High
LOCTITE
®
268 is a high strength version of an anaerobic
threadlocking material. It is supplied as a wax-like semi-solid,
conveniently packaged in a self-feeding stick applicator. As
with liquid anaerobic products, this material develops its cured
properties in the absence of air when confined between close
fitting metal surfaces. It achieves consistent strength and can
be used on a variety of metal substrates. It is particularly well
suited for applications where a liquid product may be too fluid
to stay on a part or be difficult to apply. It stores easily and
allows for direct contact to a threaded part during application to
ensure even coverage.
TYPICAL PROPERTIES OF UNCURED MATERIAL
Specific Gravity @ 25 °C 1.10
Melting Point, °C >80
Unworked Penetration, ISO 2137, 1/10 mm 90 to 140
LMS
Lubricity, K-Factor:
3/8 x 16 zinc phosphate & oil nuts and bolts:
22.2 kN tension, control (no product) 0.18
22.2 kN tension, with product 0.21
26.7 kN tension, control (no product) 0.19
26.7 kN tension, with product 0.21
(In critical applications, it is necessary to determine
the K-Factor independently. Loctite makes no
warranty of specific performance on any individual
fastener)
TYPICAL CURING PERFORMANCE
Cure Speed vs. Substrate
The rate of cure will depend on the substrate used. The graph
below shows the breakloose strength developed with time on
3/8 x 16 degreased steel nuts & bolts compared to different
materials and tested according to ISO 10964. All samples
pre-torqued to 5 N·m. Product applied to bolts only.
% of Full Strength on Steel
Cure Time
100
75
50
25
0
5min10min 30min 1h 3h 6h 24h 72h
Zinc Phosphate & Oil
Steel
Zinc Dichromate
Stainless Steel
Cure Speed vs. Temperature
The rate of cure will depend on the temperature. The graph
below shows the breakloose strength developed with time at
different temperatures on 3/8 x 16 degreased steel nuts & bolts
and tested according to ISO 10964. All samples pre-torqued to
5 N·m. Product applied to bolts only.
% of Full Strength on Steel
Cure Time
100
75
50
25
0
5min10min 30min 1h 3h 6h 24h 72h
40°C
22°C
5°C
Cure Speed vs. Activator
Where cure speed is unacceptably long due to large gaps,
applying activator to the surface may improve cure speed.
However, this can reduce ultimate strength of the bond and
therefore testing is recommended to confirm effect. The graph
below shows the breakloose strength developed with time
using Activator 7471 and 7649 on 3/8 x 16 zinc dichromate
nuts and bolts and tested according to ISO 10964. All samples
pre-torqued to 5 N·m. Product applied to bolts, activator to
nuts.
% of Full Strength on Steel
Cure Time
100
75
50
25
0
5min10min 30min 1h 3h 6h 24h 72h
Activator 7649
No Activator
Activator 7471