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This paper presents the performance of uncoated carbide cutting tool when machining cast iron in dry cutting conditions. Experiments were conducted at various cutting speeds, feed rates, and depths of cut according to Taguchi method design of experiment using a standard orthogonal array L₉(3⁴). The effects of cutting speeds (100-146 m/min), feed rates (0.20-0.35 mm/tooth) and depths of cut (1.0-2.0 mm) on the tool life, surface roughness and cutting forces were evaluated using ANOVA. Results showed that the effects of cutting speed, depth of cut and the feed rate were similar affecting the failure of the carbide cutting tools within the range of tested machining parameters. The contribution of cutting speed, feed rate, and depth of cut in controlling the tool life were 32.12%, 38.56% and 29.32% respectively. Whereas, the cutting speed was the main factor influencing the average surface roughness (R_a) value followed by feed rate. These factors contribute 60.53% and 35.59% respectively to the R_a value. On the other hand, cutting forces generated were greatly influenced by the depth of cut (66.52%) and the feed rate (32.6%). Cutting speed was found insignificant in controlling the generated cutting forces.

This work aims to investigate the effect of two different counterdisc materials, i.e. gray cast iron (GCI) and ductile gray cast iron (DGCI) on tribo behavior of non-commercial frictional materials (NF1, NF2, NF4, and NF5) and two other chosen commercial brake pads (CMA and CMB) under dry sliding contact conditions. The four non-commercial frictional materials were fabricated with various percentages of phenolic binder resin (15 and 20 vol.%) and reinforced with steel fibers (15 and 20 vol.%) using hot press molding methods. Tribo tests were carried out using a small-scale tribo-tester of pad-on-disc type. Friction coefficient and wear of non-commercial and commercial brake pads were measured against each counterdisc (GCI and DGCI) and compared. Then, the friction and wear characteristic are discussed by comparing the experimental results obtained for each kind of cast iron.

The results showed that maximum friction coefficient (0.4–0.5) of brake pad was attained at 2.22 MPa applied pressure and 2.1 m/s sliding speed when the frictional brake pad materials were tested against DGCI disc rotor. Meanwhile, similar wear rates for all frictional brake pad materials were sustained at higher applied pressure and sliding speed when tested against either type of rotor discs (GCI and DGCI).

The results on the other hand, indicated that non-commercial materials NF1 and NF4, gave better wear resistance compared to other frictional pad materials. NF2 exhibited the lowest wear resistance when tested against GCI and DGCI rotor disc at all applied pressure and sliding speeds. The latter result is referred to the low percentage binder resin in the friction material NF2.

The cast iron of different graphite shape was tested with respect of its microstructural and mechanical behavior. The original combinatorial method was applied in the quantitative metallographic assessment of cast iron microstructure. The Forster's elastomat was used for the assessment of the logarithmic vibration decrements, by means of resonance curve method. Then the same samples were tested by means of the modified low cycle fatigue method (MLCF) in order to determine the mechanical parameters. It was possible to ascertain that the quantitative relationship between damping capacity and proposed synthetic stereological parameter of graphite form obtained as exponential relation, simultaneously means that the logarithmic vibration decrement exponentially increases with the increase of square root from the quotient of relative graphite area and average chord of graphite precipitates. It was possible to ascertain also that the best part of remaining mechanical characteristics determined by means of (MLCF) method decreases with the increase of stereological parameter ξ = (S_v/l)^1/2.