UGIMA® 4104 Annealed

UGIMA® 4104 has excellent ability to withstand corrosion in certain environments. Its corrosion resistance is typical of ferritic stainless steel and is similar to that of 4104 in every respect; its corrosion resistance is similar to that of a 430 ferritic stainless steel, but it is impaired by the high sulphur content in environments liable to cause pitting or crevice corrosion.

contact the supplier for these types of environments

This grade is appropriate for all office equipment applications.

The use of UGIMA® 4104 is compatible with all the fluids, lubricants, oils and greases used in the machining industry.

However, UGIMA® 4104 is not recommended for use in marine environments and highly oxidising chemical environments.

Optimum corrosion resistance is obtained where a surface is free from all traces of machining oil or foreign particles (of iron for example).

UGIMA® 4104 is pickled in the same way as 4104 ferritic steel. This also applies to decontamination.

Note: the corrosion resistance of a stainless steel depends on many factors related to the composition of the corrosive atmosphere (chloride concentration, presence or absence of oxidizing agents, temperature, pH, agitation or no agitation, and so on), as well as to the preparation of the material (surfaces free from metal particles, surface finish such as hardening, polishing, and so on). Precautionary measures should also be taken for certain tests such as the saline mist test (French standard NFX 41002): for example marking labels that might cause corrosion run-outs and reduce the test resistance time should not be used on the sample.

The performance of UGIMA® 4104 in machining is exceptionally good, due to the optimisation of the inclusion population. This is true not only for very high speeds and severe cutting conditions, as a result of the UGIMA®, process, but also for low speeds and less severe cutting conditions, because of the new improvements achieved through this latest development. UGIMA® 4104 is therefore particularly appropriate for screw machining, as its improved machinability is effective through an extensive range of cutting conditions and machining operations. Its performance is based on extremely good chip breakability, extended tool life and excellent surface finish.

The cutting conditions shown in the tables below are those which we established in the trial phase of the development of UGIMA® 4104.

If you would like to use the grade to best advantage for your components and working environment, contact our Technical Service.

UGIMA® 4104 has a soft ferritic structure after being treated up to approximately 830°C. Above this temperature, it forms austenite, which is transformed into martensite by cooling: approximately 50% martensite maximum after treatment to about 1100°C.

Forging: UGIMA® 4104 can be forged.

It has a low flow stress (hot hardness) similar to that of a type 1.4016 (430) ferritic stainless steel, i.e. approximately 50% of that of type 1.4301 (304) austenitic stainless steel. Heating: between 1100°C and 1250°C; minimum forging temperature: 950°C After forging: two-phase ferrite + martensite structure, to be softened, if required.

Available products:

This grade is difficult to weld.

As with all semi-ferritic grades, there are various risks in welding UGIMA® 4104 if certain precautionary measures are not taken (hydrogen induced cold weld cracking, lack of weld ductility, intergranular corrosion, etc.). This operation should therefore be particularly rigorous.

To minimise the risks of cold weld cracking in a heat-affected zone [and in a weld metal zone, in the event of homogenous welding or welding without filler material], the parts should be preheated to between 150 and 230°C to remove the hydrogen present in the base metal and minimise tensile stress on cooling. If coated electrodes are used, they should be thoroughly dried to ensure that no hydrogen is supplied in the form of water vapour. For the same reasons, in arc welding, the shielding gas must not contain H₂.

After welding, to restore the resilience of the heat-affected zones [and the weld metal zones, in the event of homogenous welding or welding without filler material], the martensite should undergo a post weld annealing heat treatment at 760°C (1 hour) + quenching to transform it into ferrite + carbides. If there is a risk of the welded components being distorted during hardening, they must be cooled slowly in an oven to 600°C before mandatory quenching to avoid any risk of embrittlement at T < 500°C. To ensure improved weld bead resilience during arc welding, the shielding gas must not contain N₂ and CO₂ is not recommended. In general, the only shielding gas recommended is argon (plus 2% of oxygen for MIG welding only).

Finally, it is difficult to prevent intergranular corrosion in a heat-affected zone [and in a weld metal zone, in the event of homogenous welding or welding without filler material] and the risk is even greater when high welding energy is used. The welding energy should therefore be minimised to reduce grain boundary chrome depletion by Cr23C6 precipitation.

If filler metal is required, a homogeneous ferritic filler (430L, or 430LNb for welding thicknesses < 3 mm), or an austenitic filler (ER308LSi, 309LSi, etc.), or a duplex filler (ER312) can be used. The austenitic and duplex filler metals eliminate the risks of cold weld cracking and intergranular corrosion in a weld metal zone, but not in a heat-affected zone. Preheating and post welding heat treatment are therefore required in all cases. Due to the large amount of S in UGIMA® 4104, it is not advisable to use an "Ni base" filler wire, as is sometimes recommended for welding AISI430 semi-ferritic grades (risk of thermal cracking).