Qingdao Haier New Material PC/ABS NH-9018G10 is a short-glass-fibre-reinforced polycarbonate/acrylonitrile-butadiene-styrene alloy. The suffix G10 in the grade code is consistent with a nominal 10 wt% glass-fibre loading; however, the supplier’s English-language technical datasheet for this exact configuration is not fully available in public repositories, and numerical values presented here must be confirmed against a lot-specific certificate of analysis or the original Chinese-language datasheet before tool qualification. In this alloy system, the polycarbonate phase contributes heat resistance and impact strength, the ABS phase contributes melt processability and chemical resistance, and the dispersed short glass fibre raises tensile modulus, flexural modulus, and heat deflection temperature while lowering mould shrinkage anisotropy relative to unfilled PC/ABS. The actual glass loading, fibre diameter, and sizing chemistry are proprietary; therefore, published data for this specific configuration is limited.

Table 1 lists representative public-domain ranges for 10 wt% glass-fibre PC/ABS and an unreinforced PC/ABS reference. These ranges are not NH-9018G10 lot certifications.

The data in Table 1 illustrate the expected direction of property change when a 10 wt% short-glass fibre is introduced into PC/ABS. The reduction in notched impact strength relative to unfilled PC/ABS is particularly relevant in snap-fit designs and screw bosses; reverse-engineering from an unfilled part can underestimate the local stiffness at a boss root while overestimating the allowable snap undercut strain. Grade-specific melt flow rate, tensile strength, and flame classification must still be obtained from the supplier because glass-fibre loading alone does not determine these values.

What processing parameters govern melt stability in NH-9018G10?

Melt processing of glass-reinforced PC/ABS is constrained by two competing degradation mechanisms: hydrolysis of the polycarbonate phase when residual moisture exceeds approximately 0.02 wt% and thermal-oxidative chain scission in the styrene-acrylonitrile phase during prolonged residence at elevated temperature. Drying in a closed-loop desiccant dryer with a dew point of -30 °C or lower at 80 °C to 100 °C for 3 h to 4 h is therefore standard before injection moulding. When ambient relative humidity exceeds 60%, dried resin should not be exposed to plant air for more than 30 min, and hopper loaders should be fitted with dry-air purging. Incoming moisture can be checked against ISO 15512:2019.

Barrel zone set points on a general-purpose reciprocating screw with L/D 20:1 to 24:1 are typically 240 °C in the feed zone, 250 °C to 260 °C in the compression zone, 260 °C to 270 °C in the metering zone, and 260 °C to 270 °C at the nozzle. Melt temperature measured by an insertion pyrometer should not exceed 280 °C; above this threshold surface silver streaks, black specks, and molecular weight reduction become more likely in PC-rich domains. Residence time at melt temperature should be held below 5 min, including hot-runner dwell, because glass-filled PC/ABS can develop carbon deposits on stagnant flow surfaces.

A screw with a non-return valve and a compression ratio not exceeding 2.4:1 is preferred. A metering section of 4 to 5 flights and a low-shear mixing section improve glass-fibre distribution without excessive fibre attrition. Back pressure between 3 MPa and 7 MPa is applied to maintain shot-to-shot density; higher back pressure reduces melt-temperature stability and shortens retained glass-fibre length, shifting Charpy impact downward. Injection speeds from 200 mm/s to 400 mm/s linear screw velocity are used for thin-wall fills, but very high gate shear can align fibres along the gate direction and increase differential shrinkage.

Mould temperature is maintained at 70 °C to 90 °C. The upper end of the range improves textured-surface reproduction and weld-line healing but increases cycle time and cooling-water load. Ejector plate and cavity pressure sensors are recommended for process monitoring because glass-filled PC/ABS shows a sharper viscosity increase near the solidification boundary than unfilled PC/ABS. Mould release should be arranged without amine-functionalised silicones or amine-based additives; amine moieties can catalyse polycarbonate hydrolysis or aminolysis at processing temperatures.

Regrind content should be limited to 20 wt% or less. Each extrusion or injection pass reduces the number-average glass-fibre length, lowers tensile modulus and notched impact strength, and broadens shrinkage variability. If regrind is used, it should be dried under the same conditions as virgin resin, stored in sealed containers with desiccant, and blended with virgin material at an automatic gravimetric dosing station to avoid lot-to-lot density variation.

For electronic control unit housings, automotive interior attachment brackets, and appliance structural frames, NH-9018G10 is typically positioned between unfilled PC/ABS and 20 wt% glass-fibre PC/ABS. The 10 wt% glass loading retains enough matrix-rich surface for gloss and snap-fit ductility while raising flexural modulus into a range suitable for load-bearing mounts. In interior automotive parts, the lower post-mould shrinkage permits tighter gap and flush tolerances than unfilled PC/ABS; validation should still include OEM-specific grain retention requirements, DIN 75201 fogging for the compounded colourant system, and ISO 105-A02 colour-change assessment after heat ageing. Since the grade code does not contain a flame-retardant marker, UL 94 V-0 at 1.5 mm cannot be assumed; a current UL Yellow Card or supplier certificate is required before the material is used in information-technology equipment enclosures evaluated to IEC 62368-1.

Electrically dissipative or conductive compounds should not be substituted on the basis of glass content alone. Surface resistivity must be measured according to IEC 62631-3-2 if electrostatic discharge control is required. Similarly, laser transmission welding at 980 nm can be disrupted by glass-fibre scattering; trials should compare the optical transmission of natural and black laser-transparent grades, and joint strength should be tested according to ISO 527-1/-2 on welded plaques rather than on bulk specimens.

Compared with semicrystalline glass-reinforced polyamides, NH-9018G10 is expected to have lower moisture-induced dimensional change but lower continuous heat resistance in hot-oil or hot-water environments. If a part is exposed to ethylene glycol at temperatures above 80 °C, stress-crack resistance must be evaluated with the actual coolant mixture under constant strain; PC/ABS is generally less resistant to glycol stress cracking than glass-filled polyamide. This difference can be decisive in under-hood coolant-system brackets.

When dimensional stability requirements exclude unreinforced grades

When a housing or frame must maintain flatness after ejection and through thermal cycling, glass fibre changes the shrinkage field from approximately isotropic to mildly anisotropic. Mould shrinkage parallel to flow is lower than shrinkage normal to flow for 10 wt% glass-filled PC/ABS, producing differential contractions that can bow long ribs or cause sink near bosses. Gate location should therefore be selected so the largest flow path follows the dimension with the tightest tolerance; weld lines and knit lines should be moved away from screw bosses and load-bearing fillets. In tool trials, shrinkage should be measured on plaques or cavity inserts according to ISO 294-4:2018, and the difference between parallel and normal shrinkage should be recorded at several points because gate symmetry alone does not guarantee balanced flow in glass-filled compounds.

Compared with unfilled PC/ABS, the expected increase in tensile and flexural modulus permits thinner walls for a given deflection limit under ISO 178. However, the reduction in notched impact strength means that snap-fit undercuts designed for unfilled PC/ABS may fail if the same strain is imposed at the same wall thickness. Snap-fit design should include a minimum root radius of 0.5 mm, gussets or strain-relief slots, and moulded-in flow orientation that avoids fibrous skins at the snap root. If the part is painted, flame-treated, or plasma-treated after moulding, the treatment must be validated because glass fibres at the surface can alter adhesion and expose fibre ends after abrasion.

Relative to mineral-filled PC/ABS, glass-fibre reinforcement gives a higher stiffness-to-density ratio and generally better impact strength at similar modulus, but mineral fillers can produce more isotropic shrinkage and lower warpage in large flat panels. The choice between NH-9018G10 and a mineral-filled PC/ABS therefore depends on whether flatness or snap-fit strength is the dominant requirement. For large thin-wall brackets, mineral-filled grades may be preferred for dimensional stability; for structural ribs and bosses, the glass-filled grade may allow thinner nominal wall stock without exceeding deflection limits.

If the application requires UL 94 V-0 at 1.5 mm, the grade should be replaced by a halogen-free flame-retardant PC/ABS or a flame-retardant glass-filled PC/ABS verified by the supplier. Flame-retardant additives can further reduce notched impact strength and alter melt viscosity; therefore switching from an unfilled flame-retardant PC/ABS to NH-9018G10 without repeating UL end-product testing is not permitted under IEC 60695-11-10 unless the component-level certification is maintained by the final equipment manufacturer.

Weld-line strength and fibre orientation at 10 wt% loading

Short-glass fibres at a converging weld line orient parallel to the knit line, producing a resin-rich or fibre-depleted boundary layer. Published studies on short-glass-fibre thermoplastics report weld-line tensile-strength reductions of 30% to 50% relative to unwelded bulk material. For ribbed brackets, boss-mounted housings, or gear covers, the tool should be gated to create a single advancing flow front where possible. If a weld line is unavoidable, local wall thickness can be raised by 0.2 mm to 0.4 mm in the weld zone, and mould temperature can be increased to 90 °C to improve flow-front healing, though this lengthens cycle time.

Melt viscosity should be measured on the actual lot with ISO 1133-1:2022 at the supplier-specified temperature and load. High melt viscosity may increase fibre orientation but can reduce surface jetting and improve uniformity; low viscosity improves filling but can decrease weld-line healing and increase flash in worn tools. Mould-filling simulation should use fibre orientation models calibrated against tensile and flexural data obtained to ISO 527-1/-2 and ISO 178. Without measured fibre-length distribution after injection, predicted weld-line strength can deviate by more than 15% relative to physical test results. Validation of a first-article tool should therefore include cross-sections through the weld line examined by optical microscopy after polishing, because tensile data alone can conceal a weak near-surface layer.

In chemical exposure evaluations, the polycarbonate phase of NH-9018G10 governs stress-crack resistance. Aromatic hydrocarbons, ketones, esters, chlorinated solvents, and some glycol ethers can induce environmental stress cracking in stressed parts. Moulded test bars should be immersed or wetted with the actual service fluid under ISO 22088-3 constant-strain conditions, followed by tensile or flexural retention testing to ISO 527-1/-2 or ISO 178. Alcohol-based cleaners are generally less aggressive but can still craze textured surfaces after repeated exposure; for interior electronic housings cleaned more than 50 cycles in service, the final surface chemistry and texture depth should be qualified with the intended cleaning agent.

Ultraviolet exposure and long-term heat ageing should not be inferred from short-term HDT data. If the part is exposed to direct sunlight or UV-A lamps, a UV-stabilised grade or painting/coating may be required; glass reinforcement does not provide UV protection. Long-term heat ageing at 85 °C to 100 °C for PC/ABS can embrittle the ABS phase and reduce notched impact strength after several hundred hours; ISO 4577 or OEM-specific heat ageing should be performed before warranty life is claimed.

Table 2 summarises the compliance and incoming-inspection checks that should be attached to a NH-9018G10 first-article approval.

Before series production, the lot-specific certificate of analysis should be compared with the first-article trial data for density, tensile modulus, notched impact strength, and HDT according to the ISO methods cited in Table 2. The moulding process card should record nozzle melt temperature, screw recovery time, cushion, fill time, peak injection pressure, and mould temperature; deviations greater than 5 °C in melt temperature or 10% in fill time should trigger a new capability run. Incoming resin should be tested for moisture and melt flow according to ISO 15512:2019 and ISO 1133-1:2022, and moulded parts intended for automotive interior use should be subjected to at least 20 thermal cycles from -40 °C to 85 °C with dimensional inspection before and after cycling.