*Development of Functionally Gradient Cu-Sn-Ni Alloy Using GTA Heat Source DOI: http://dx.doi.org/10.5772/intechopen.86315*

resistance, hardness, corrosion resistance, thermal conductivity, etc., of various alloys can be improved by the application of SMP. C Paul [2]. A schematic of SMP is shown in **Figure 1**.

This chapter discusses an investigation on the effect of Ni content on the hardness, the wear rate and the coefficient of friction of the surface alloyed Cu-Sn bronze alloy. As no previous works have been reported in the literature on the effect of Ni content on the hardness and the wear behavior of the surface alloyed bronze alloy, the present research work is undertaken. In the present study, the Sn content of the alloy was kept constant at 10 wt % and the Ni content was varied. The bronze substrates are coated with Ni of varying coating thickness (80, 120, 160 and 200 μm) using electroplating technique. The surface alloying process was carried out on the Cu-Sn bronze alloy coated with Ni. The GTA was used as the heat source. The GTA process variables, current (I), electrode diameter (eΦ), arc length (l), electrode angle (eθ), traverse speed (u) and argon flow rate are kept constant during the surface alloying process. The GTA process variables used in this study are reported in **Table 1**. The Ni concentration profiling was carried out for the surface alloyed samples. The Ni concentration was measured on the surface as well as along the depth of the modified layer formed in the surface alloying process using EDAX

**Figure 3.** *Cu-Sn alloy with and without Ni coating.*

**Figure 4.** *Cu-Sn alloy surface modified with Ni.*

*Mechanics of Functionally Graded Materials and Structures*

**Process variable Value Unit** Current 200 A Electrode diameter 2.4 mm Arc length 1.5 mm Electrode angle 180 ° Traverse speed 1 mm/s Argon flow rate 12 l/min

**80**

**Figure 2.** *Experimental setup.*

**Table 1.**

**Figure 1.**

*Surface modification process.*

*GTA process variables.*

analysis. Microstructural examination, hardness measurement and wear measurements were carried out for the substrate and for the specimen surface alloyed with Ni. **Figure 2** shows the experimental setup.

**Figure 3** shows the Cu-Sn alloy substrate with and without Ni coating and **Figure 4** shows the surface modified Cu-Sn-Ni alloy.
