Nanjing Delong PC/ABS CS103 is a pelletized polycarbonate/acrylonitrile-butadiene-styrene alloy in the manufacturer’s CS series of injection-moulding compounds. The CS103 model designation identifies a general-purpose, non-flame-retardant grade with a controlled melt-viscosity profile for thin-wall technical parts. It is specified for electrical housings, appliance control panels, office automation covers, and interior automotive trim where dimensional stability, impact resistance, and processability are required. Manufacturer-certified single-point data for this exact grade are not reproduced in this technical overview; therefore, quantitative values below are presented as representative of commercial PC/ABS compounds of the same nominal viscosity class and must be confirmed against the Nanjing Delong certificate of analysis before part qualification.

What Drying and Melt-Processing Limits Apply to CS103?

Pellet moisture is the first processing boundary. PC/ABS absorbs moisture through the amorphous matrix; pellets exposed to 23 °C and 50 % RH can reach 0.2 wt% to 0.35 wt% moisture. Before injection moulding, the material is dried in a desiccant dryer at 80 °C to 100 °C for 2 h to 4 h until residual moisture is below 0.02 wt%. Pre-drying is required at room humidity above 60 % RH. A drying hopper dew point below -30 °C is typical; if the dew point rises above -20 °C, the required drying time increases. Drying hoppers with molecular-sieve desiccant beds are preferred over hot-air ovens. Airflow should be at least 0.15 m³/min per kg/h of pellet throughput, and return air temperature should remain above 60 °C to prevent re-condensation. Residual moisture above 0.03 wt% hydrolyzes the polycarbonate phase during melt processing, causing splay, silver streaking, and reduced weld-line strength.

Machine settings are established on a single-screw injection-moulding machine with a general-purpose screw of 20:1 to 25:1 length-to-diameter ratio and 2.0:1 to 2.5:1 compression ratio. Barrel set points are typically reverse-profile: rear 230 °C to 240 °C, middle 250 °C to 260 °C, front 260 °C to 270 °C, nozzle 260 °C to 275 °C. Melt temperature below 235 °C produces high melt viscosity and flow hesitation; melt temperature above 285 °C degrades the butadiene phase. The shot should occupy 30 % to 70 % of barrel capacity and barrel residence time should not exceed 10 min. Back pressure is maintained at 5 bar to 15 bar hydraulic, and screw peripheral speed is kept below 0.5 m/s to limit shear heating. Mould temperature is held between 60 °C and 90 °C to balance cycle time against surface gloss, dimensional stability, and frozen-in stress.

Production-scale failure modes include moisture regain when dried material is left in an open hopper at 70 % RH: pellet moisture can return to 0.03 wt% within 30 min to 60 min, producing splay and loss of weld strength. If hot-runner channels exceed 280 °C, yellowing and black specks from degradation of the ABS phase appear after 10 min to 15 min of residence time. Injection moulding clamp force is estimated from cavity pressure: for PC/ABS, average cavity pressure is 30 MPa to 50 MPa. A part with projected area 200 cm² would require 600 kN to 1000 kN clamp force.

Representative Property Window and Test Method Cross-Reference

The following property window is compiled from published data for injection-moulding PC/ABS grades with comparable melt-flow and non-flame-retardant formulation. It is not a vendor-certified data sheet for CS103. Specifying agents should obtain the batch certificate and compare the actual melt volume-flow rate and impact values against the values below.

The tensile and flexural values follow ISO test specimen geometry: tensile specimens are type 1A per ISO 527-2, conditioned at 23 °C and 50 % RH for 88 h. Charpy specimens are type 1 with eA notch radius 0.25 mm. Because PC/ABS is notch-sensitive at low temperature, the -30 °C Charpy value is typically 40 % to 60 % lower than the 23 °C value. Linear coefficient of thermal expansion is approximately 70 µm/m·°C to 90 µm/m·°C in the flow direction, which is lower than unfilled ABS but higher than glass-filled polyamide. The UL 94 classification of this non-flame-retardant alloy is typically HB at 1.5 mm to 3.0 mm wall thickness; where V-0 at 1.5 mm is required, a flame-retardant PC/ABS grade should be selected instead. Electrical property data, such as comparative tracking index or dielectric strength, are not universally published for CS103 and should be requested for insulation applications.

Electronic enclosure design with CS103 uses wall stock from 1.5 mm to 3.2 mm. Sections below 1.2 mm require high injection velocity, accumulator-assisted filling, and pack pressure at the upper end of the 40 MPa to 70 MPa hydraulic range. Gate diameter is held between 0.8 mm and 1.5 mm for edge gates; gate placement should avoid weld lines at snap-fit bosses. Draft angle is 0.5° to 1.0° on textured surfaces. Venting depth at the parting line is limited to 0.02 mm to 0.04 mm to avoid flash. Rib root radius should not fall below 0.25 mm because the notch-sensitive PC/ABS matrix can enter brittle failure under impact. Rib thickness should not exceed 50 % of the nominal wall to avoid sink marks, and metal inserts should be preheated to 100 °C to 120 °C to reduce residual stress. Because CS103 is amorphous, it gives lower anisotropic shrinkage than semi-crystalline glass-filled polymers, permitting tighter flatness tolerances in multicavity tools.

When Nanjing Delong PC/ABS CS103 Replaces Coated Metal, Unfilled PC, or Glass-Filled Nylon in Equipment Housings

Compared with coated metal, CS103 reduces part mass and consolidates snap-fit and boss features, but it does not provide equivalent electromagnetic shielding or flame resistance. For EMI-sensitive equipment, conductive coatings or metal inserts are required. Compared with unfilled polycarbonate, CS103 processes at a lower melt temperature by approximately 20 °C to 30 °C and fills thin sections more readily because of the ABS phase; however, its heat deflection temperature is lower by roughly 20 °C to 30 °C. Compared with glass-filled PA66, CS103 offers lower warpage and lower moisture-induced dimensional change, but it has lower tensile strength and lower continuous-use temperature under load.

Chemical exposure differs from other products. CS103 is not recommended for continuous contact with aromatic hydrocarbons, ketones, aliphatic solvents, or strong alkali solutions. Environmental stress cracking is observed with toluene, methyl ethyl ketone, and certain brake fluids. For exterior applications, unpigmented CS103 requires UV stabilization or a co-extruded ASA cap layer because polycarbonate yellowing and loss of gloss occur after prolonged UV exposure. The material is also not recommended for continuous use above 60 °C in hot water due to hydrolysis; repeated steam sterilization requires unfilled polycarbonate or polysulfone. If decorative electroplating is required, the supplier should confirm the grade’s etchability and plate adhesion because not all CS-series materials are electroplating grades.

Regulatory declarations depend on the final formulation and pigment package. Suppliers should provide batch-specific documentation for RoHS 2011/65/EU and REACH SVHC compliance. For food-contact or medical use, migration testing under EU 10/2011 or FDA 21 CFR 177.1580 is required because a generic PC/ABS compound does not automatically satisfy these requirements. The non-flame-retardant CS103 formulation is not intended for applications requiring UL 94 V-0 at 1.5 mm or glow-wire ignition resistance to IEC 60695-2-11.