本研究中藉由選擇適當的前處理液和無電鍍鎳鍍液，在鐵粉上析鍍一層具有完整包覆性的鍍層；並改變析鍍的參數，來控制無電鍍鎳鍍層的析鍍量。另外，本實驗也探討在不同的熱處理條件下，經過無電鍍鎳處理後之鐵粉的化學組成及結構變化的現象。熱處理分別為在真空氣氛中，或10﹪H2 + 90﹪Ar的混合還原氣氛中進行，升溫至所需溫度，持溫0、90、180分鐘後，空冷或水淬至室溫；接著將熱處理後之粉末之表面型態、化學成份以及結構組織變化，分別以掃瞄式電子顯微鏡(SEM)、能量散佈光譜儀(EDS)以及X光繞射分析儀等加以分析。
實驗結果顯示，未經過前處理液處理過之鐵粉，在做無電鍍鎳處理後，會有析鍍不均勻的現象產生。而經過前處理過的粉末，在經無電鍍鎳後，可以得到披覆性較佳的鍍層，且此鍍層屬非晶質結構。當粉末的重量為定值時，可成功的利用改變鍍液體積來控制無電鍍鎳層的析鍍量。
鐵粉經無電鍍鎳處理後，在10﹪H2 + 90﹪Ar的混合還原氣氛中，或是在真空中，在不同溫度下加以熱處理，所產生的化學成份及相變化的現象雷同。在熱處理過程中，鍍鎳層與其內之鐵核發生鐵、鎳元素相互擴散的結果，促成化學成份改變與相變化。隨著熱處理溫度之提高以及熱處理時間的延長，鐵及鎳互溶的程度逐漸增加，最後達到均值化的效果。在熱處理過程中，也會促成鍍鎳層結晶化以及結構組織逐步轉化的現象。

The purpose of this study was to form uniform Fe-Ni powders (the content of Ni was about 30-60 wt%) by depositing nickel onto the iron powders through the electroless-nickel plating technique and then undergoing appropriate heat treatment process. The whole plating process involved two steps: pre-plating and plating treatments. In the pre-plating treatment, nickel chloride solution containing NaF was utilized to activate the surface of as-received iron powders and further adsorb some metallic fine nickel particles for purpose to achieve better plating performance in the following nickel-plated process. Ni-B electroless nickel-plated solution was employed in the nickel plating process. After plating, heat treatment was conducted to homogenize the as-plated powders. Different annealing temperatures ranging from 500-900℃ were performed to investigate the effect of temperature on the changes of chemical composition and crystal structure of electroless nickel-plated iron powder.
The experimental results showed that the pre-plating treatment was more advantage for depositing of a uniform and compact nickel layer around the iron powders during the plating process. X-ray results show that the original iron powder was γ phase and after plating amorphous Ni deposited around γ-Fe. After heat treatment, amorphous Ni would crystallize toγ-Ni, and then Fe, Ni would gradually solute and transform to γ-(Fe, Ni) phase in the boundary of Fe and Ni. As the increasing of heating temperature, the solvability of Fe and Ni would increase, so the γ-(Fe, Ni) phase would gradually appear. And the diffraction angle 2θ of γ-(Fe, Ni) would Shift from 43.76° to 43.52° in a temperature raging from 700℃ to 900℃.γ-Fe and γ-Ni would completely solute and then transform to γ-(Fe, Ni) in 900℃,180 minutes heating process.

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