Öz
Geleneksel olmayan imalat yöntemlerinden bir tanesi olan kimyasal işleme yöntemi uygun kimyasal
aşındırıcı içerisinde malzemenin kontrollü olarak aşındırılarak şekillendirilmesi olarak tanımlanabilir.
Yöntem her türlü malzemenin işlenmesinde rahatlıkla uygulanmakta ve yaygın olarak uçak, elektronik ve
medikal endüstrilerinde hassas ve karmaşık şekilli parçaların imalatında kullanılmaktadır. Mikro işleme
yöntemi olarak da kullanılabilen kimyasal işleme yöntemi mikro elektro-mekanik sistemler için mikron
boyutunda parçaların imalatında da kullanılabilmektedir.
Bu çalışmada, X5CrNi18-8 paslanmaz çeliğinin kimyasal işlenmesi konusu deneysel olarak araştırılmıştır.
Mühendislik uygulamalarında yaygın olarak kullanılan paslanmaz çeliğin kimyasal işlenmesi için demir
klorür (FeCl3) kimyasal aşındırıcısı kullanılmıştır. Daldırma metodu ile kimyasal işleme yönteminde
belirlenen işleme parametreleri kimyasal aşındırıcının yoğunluğu ve kimyasal işleme sıcaklığıdır. Bu amaçla
28°Bé, 32°Bé ve 36°Bé kimyasal aşındırıcı yoğunlukları seçilmiş; kimyasal işleme sıcaklıkları olarak 30 °C,
50 °C ve 70 °C kabul edilmiştir. Kullanılan kimyasal işleme sıcaklıklarından 70 °C deneysel çalışmalarda ilk
defa kullanılmıştır. Belirlenen işleme parametrelerinin aşındırma miktarı ve yüzey pürüzlülüğü üzerine
etkileri araştırılmıştır.
Yapılan deneysel çalışma sonucunda 32°Bé yoğunluklu FeCl3 çözeltisinin işleme derinliği ve yüzey
pürüzlülüğü açısından uygun olduğu belirlenmiştir. Ayrıca kimyasal işleme sırasında seçilen işleme
sıcaklığının artması ile işleme derinliğinin arttığı görülmüştür. Yüzey kalitesi açısından kullanılan her üç
aşındırıcı yoğunluğu da benzer sonuçlar vermiştir. Yüksek işleme sıcaklıklarında yüzey pürüzlüğü
değerlerinin azaldığı görülmüştür
Anahtar Kelimeler
Öz
Chemical machining is applied in many
manufacturing industries such as electronics,
aerospace, medical and aotumotive to etch, cut or
engrave metal plates. The process relies on
controlled corrosion of workpiece material in acidic
or alkaline etchant. The process is also called in
different names like chemical etching, etching,
chemical milling, wet etching in literature. It can be
used to shape steal titanium, nickel, copper and its
alloy,aluminium and its alloys and every kind of
materials to manufacture stencils, brake motor, fuel
cell, printed circiut boards, plates, stamping dies,
signs, jewelry, plaques, printing plates etc. The
process is known with different names in literature
such as chemical milling, etching, chemical etching,
wet etching etc.
The history of chemical machining goes back to
Ancient Egypt, it was used to produce jewelry from
copper with citric acid solution. Development of
electronics industry made the process more
attractive, because high precision and small parts
were heavily required. Main industrial application
of chemical machining started in 1950’s, the process
was used to etch aluminium parts for aircrafts and
rockets.Nowadays, chemical machining is used as
micromachining in the production of micro electromechanic
system part as well.
The major advantage of chemical machining is
producing high precision parts in a short machining
time with low production cost. The process does not
require special tooling. Moreover, the product parts
are burr free. However, chemical machining is not
environmentally friendly machining process because
of hazardous effects of etchants on environment.
This problem is almost overcomed by using
regeneration of waste etchant and recovery of
etched material. The most suitable system is
combination of regeneration and recovery
simultaniously.
The main parameter of chemical machining is the
selection of suitable etchant for workpiece material.
Various chemical etchants can be named for this
purpose. Ferric chloride (FeCl3) etchant is
commonly used for iron based alloys, copper and
aluminium. This etchant is called “universal
etchant” due to wide application in chemical
machining .Copper chloride and alkaline etchants
are widely used for copper etching in electrronics
industry.
Stainless steel is commonly etched with FeCl3
etchant solution. Various studies have been carried
out to investigate etching performance of this
material. These studies concluded that FeCl3
etchant is the most suitable etchant solution for
chemical machining of stainless steel. The etchant
conmcentration sould be around 36-42°Bé at 50 °C
etching temperature. The additions of some additives
such as hydrochloric acid, also improves etching
performance in chemical etching of stainless steel.
However, there are stil some problems about
chemical machining of this material such as the real
influence of etchant concentration and etching
temperature on etch rate and surface roghness.
The purpose of this study is to investigate the
chemical machining behaviour of XCrNi18-8
stainless steel with FeCl3 etchant solution. Three
etchant concentrations 28°Bé, 32°Bé ve 36°Bé of
FeCl3 were selected. The other parameter was
etching temperature, values of 30°C, 50°C and 70°C
were applied for experimental study. The effects of
selected chemical machining parameters on etch
rate and surface roughness were experimentally
investigated.
The experimental study was carried out in a beaker
as immersion etching method. The prepared etchant
solution was placed on hot plate with magnetic
stirrer and etching temperature was kept ± 2°C.
The total etching time was 15 mins and each
measurements of thickness and surface
roughness were taken every 5 mins. It was
concluded that etchant concentration is important
factor on etch rate and surface roughness. 32°Bé of
FeCl3 etchant produced better etch rate in
comparison to 28 and 36°Bé etchant concentrations.
Moreover, etching tempertature was effective
parameter, lower etching temperature (30°C)
provided high surface roughness. The use of higher
etching temperature gave better surface quality.
Anahtar Kelimeler
Ayrıntılar
| Diğer ID | JA46GP22DM |
|---|---|
| Bölüm | Makaleler |
| Yazarlar | |
| Yayımlanma Tarihi | 1 Haziran 2011 |
| Gönderilme Tarihi | 1 Haziran 2011 |
| Yayımlandığı Sayı | Yıl 2011 Cilt: 2 Sayı: 1 |