Reduced Ductility

The cracking susceptibility of a micro-alloyed HSLA-100 steel was examined and compared to that of a HY-100 steel in the as-received condition and after heat treatment to simulate the thermal history of a single pass weld. Slow strain rate tensile tests were conducted on samples of these alloys with these thermal histories in an inert environment and in an aqueous solution during continuous cathodic charging at different potentials with respect to a reference electrode. Both alloys exhibited reduced ductilities at cathodic potentials indicating susceptibility to hydrogen embrittlement. The results of these experiments will be presented and discussed in relation to the observed microstructures and fractography. 

Figure 6. SEM micrographs showing the reduced ductility observed at high hydrogen fugacities (region 3 of Figure 4(b)) in the parent metal of the (a) HY-100 and (b) HSLA-100 alloys and the transgranular cleavage-like (TCL) fracture morphology in (c) HY-100 and (d) HSAL-100.

Impurities above maximum levels indicated in published specifications (42) can affect the properties of the finished casting. Silicon, for example, is normally added to many of the copper—beryllium casting alloys to promote fluidity, but excess silicon reduces ductility. Excessive zinc, tin, phosphorus,... 

Zinc chloride 97-100% efficiency (higher production rates) (lower energy costs) bright finish accept most chromaters low cost chemistry Reduced ductility over. 5 mil thickness reduced plate distribution high capital cost for equipment (corrosion resistance) tighter chemical control required... 

Work hardening is closely related to fatigue. In the example on fatigue given above, bending the thin steel rod becomes more difficult the farther the rod is bent. This is the result of work or strain hardening. Work hardening reduces ductility, which increases the chances of brittle failure. 

Work hardening has the effect of reducing ductility, which increases the chances of brittle fracture. 

Up to 0.1% P nsually increases strength, hardness, wear resistance and corrosion resistance and improves flow properties, but weldability may be reduced. Abnormally large amonnts of P may increase hardness, but cause cold shortness and reduce ductility and strength in most types of steel. Phosphorns is sometimes added deliberately to improve machinability or corrosion resistance of some types of steel. The presence of P can sometimes affect the high-temperatnre performance of some alloy steels. 

Alloy 201 is a low-carbon version of alloy 200. Alloy 200 is subject to the formation of a grain boimdary graphitic phase that tremendously reduces ductility. Consequently, nickel alloy 200 is limited to a maximum operating temperature of 600°F (315°C). For applications above this temperature, alloy 201 should be used. 

J. L. Illinger We only looked at one polymer with half the soft segment length. In that case the polymer showed reduced ductility and the laminate showed lowered resistance to impact. 

As for all a-p alloys, excessive aluminum, oxygen, and nitrogen can reduce ductility and fracture toughness. Excessive beta stabilizers (for example, molybdenum or vanadium) affect the stability... 

Sulfur <0.5 Reduces ductility, improves machinability. Not beneficial for corrosion resistance... 

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