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Файл:Metal corrosion. Electroplating (Защита металлов от коррозии. Гальванотехника). Учебно-методическое пособие
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Unit 13
А
В
COPPER PLATING
1. Read the international words, guess their meanings and give
the Russian equivalents.
Commercially, utilized, complex, system, modification, fluoborate,
pyrophosphate, stable, active, toxic, nature, character, decoration, cable,
beryllium, tellurium, thermal, bronze.
2. Read and translate the following verbs.
To cover, to buff, to offer, to throw, to require, to oppose,
to favor, to solder, to alloy, to theorize, to trace, to recycle, to discharge, to
exceed, to produce, to dissolve, to certify, to impair.
3. Match the English phrases from column A with the Russian
phrases in column B.
1) copper plating
2) commercially available
3) surface imperfection
4) excellent undercoat
5) easy-to-plate
substrate
6) stable supply
7) lustrous metal
8) heat treatment
9) stop-off
10) PC-board
11) steel wire
12) electrical cable
a) печатная плата
b) изолирование части детали
во время нанесения покрытия
c) стабильная подача питания
d) меднение
e) блестящий металл
f) легко электролитически
осаждаемая плата
g) поверхностный дефект
h) электрический кабель
i) превосходное грунтовочное
покрытие
j) термическая обработка
k) имеющийся в продаже
l) стальная проволока
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4. Read and translate the text. Summarize it in Russian.
Copper plating is the process in which a layer of copper is
deposited on the item to be plated by using an electric current. Three basic
types of processes are commercially available based upon the complexing
system utilized:
- alkaline- (several modifications of cyanide and non-cyanide)
complexed bath
- acid- (sulfate and fluoborate) complexed bath
- mildly alkaline- (pyrophosphate) complexed bath
With a higher current, hydrogen bubbles will form on the item to be
plated, leaving surface imperfections. Often various other chemicals are
added to improve plating uniformity and brightness. Without some form of
additive, it is almost impossible to obtain a smooth plated surface. These
additives can be anything from dish soap to proprietary compounds.
Copper is an excellent undercoat for subsequent deposits, since it is
a good metal to cover substrate defects such as holes and splinters. Buffing
copper, which is very easy to do, even improves upon its ability to be an
excellent substrate. Copper, and especially buffed copper, can provide an
easy-to-plate, highly level and bright substrate.
Copper is among the less expensive metals and is in relatively
stable supply. More leveling can be obtained for the cost of the metal
electroplated than for any other metal.
Copper has a high plating efficiency and many copper plating
processes offer good coverage and throwing power. (From
en.wikipedia.org/wiki/copper_plating)
5. Read the text again. Decide whether the following
statements are true or false.
1. Copper plating is the process when a layer of copper is deposited
on the item to be plated electrically.
2. It is slightly possible to get a smooth plated surface without some
additive.
3. Copper has a low plating efficiency and few copper plating
processes offer good coverage and throwing power.
4. There are more than five basic types of processes based upon the
complexing system utilized.
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6. Read the text. What is its main idea?
Медные покрытия, как правило, не применяются в качестве
самостоятельного покрытия ни для декоративных целей, ни для
защиты стальных деталей от коррозии. Это связано с тем, что медь в
атмосферных условиях легко окисляется, покрываясь налетом
окислов.
Однако, благодаря хорошему сцеплению осажденной меди с
различными металлами, медное покрытие применяется в
многослойных защитно-декоративных покрытиях в качестве
промежуточного подслоя, а также для защиты стальных деталей от
цементации. В гальванопластике медные осадки используются для
изготовления металлических копий, барельефов, волноводов и матриц.
Электролиты меднения подразделяют на кислые и щелочные.
Из кислых электролитов используют серно-кислые и
борфтористоводородные. Наибольшее применение нашли сернокислые электролиты, отличающиеся простотой состава,
устойчивостью и высоким выходом по току (до 100%). Недостатком
этих электролитов является невозможность непосредственного
покрытия стальных и цинковых деталей вследствие контактного
выделения меди, имеющей плохое сцепление с основным металлом.
К щелочным электролитам меднения относятся цианистые,
пирофосфатные и другие электролиты. Цианистые медные
электролиты обладают высокой рассеивающей способностью,
мелкокристаллической структурой осадков, возможностью
непосредственного меднения стальных деталей. К недостаткам
относятся низкая плотность тока и неустойчивость состава вследствие
карбонизации свободного цианида под действием двуокиси углерода
воздуха. Кроме того, цианистые электролиты характеризуются
пониженным выходом по току (не более 60-70%). (From
www.galvanicline.ru)
7. Work in pairs. Translate the following text from English
into Russian.
Copper is an active metal and so difficult to plate onto a passivated
surface, making direct plating of iron based metals difficult. Such surfaces
often require a nickel strike base coat for the copper to adhere to. The
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plating seen in chemistry classes, often obtained with a coin and copper
sulphate bath, is in fact deposition as opposed to plating. Subjecting the
surface to any wear causes the unstuck deposit to come away. Running such
a bath for longer periods, one can often see the grainy like texture of
deposition as opposed to the smooth surface of plating. Commercial platers
often use a copper cyanide-based solution to ensure a high level of copper
remains in solution. These solutions are inherently dangerous due to the
highly toxic nature of cyanide.
Cyanide based bath chemistry produces a matte finish favored for
its diffusion blocking character. If a bright surface is required, such as one
required for decoration or soldering upon, an acid bath chemistry is used.
8. Work in pairs. Interpret the following passage sentence by
sentence.
Copper is a soft, ductile, lustrous metal with a pink hue that exhibits
very high thermal and electrical conductivity. Pure copper is very soft and
malleable but can have considerable strength when alloyed with elements
such as beryllium, chromium or tellurium.
Most commonly copper is alloyed with zinc to form brass or with
tin to form bronze alloys.
Copper oxides are known in several oxidation states and can have
distinctive blue or green hues in acidic environments as opposed to dark
brown oxide products in alkaline environments. An everyday example of
this phenomenon is the green copper oxide or patina visible on the Statue of
Liberty due to the acidic rain of New York City.
Copper is one of the few metals to occur naturally as an
uncompounded mineral. Due to this fact copper’s use can be traced back to
some of the oldest civilizations on record as far back as 10,000 years ago.
It is theorized that only gold and meteoritic iron has been utilized by
civilizations longer than copper.
For plating applications copper is commonly used as an
underplating to enhance adhesion of deposits, improve electrical properties,
impair migration of alloying elements into the final plated deposit or to
improve corrosion resistance of the overall deposit. As a final deposit,
copper plating services are used for enhancing the brazing, thermal or
electrical conductivity of substrate materials, as a high temperature
lubricant, as a heat treatment stop-off or for jacketing of projectiles.
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Copper can be plated matte to bright and with a wide range of deposit
hardness and ductility.
9. Give English equivalents to the following word combinations
and learn them by heart:
стальная проволока
пассивированная поверхность
легирующий элемент
медь ковкая
щелочная среда
матовая поверхность
запатентованные составляющие
кислотная ванна
10. Give Russian equivalents to the following word
combinations and learn them by heart:
copper plating
etched goods
electrolytic precipitation
good adhesion to
production of sonotrodes
dissipating ability
low density
carbonization of free cyanide
11. Translate the following sentences into Russian.
1. Although the EPA limits the discharge of copper and copper
plating solutions, copper metal is less environmentally hazardous than
many other plated metals.
2. The waste-treatment processes for copper plating solutions and
copper containing rinse waters are well known, and in most cases easy to
accomplish.
3. Many times the copper metal and even the plating bath can be
recycled.
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4. Copper's high electrical conductivity is exceeded only by silver,
making it an excellent and inexpensive coating for products such as printedcircuit (PC) boards.
5. Copper is 'salmon pink' in colour when highly polished and can
look anything from brown to red or even black when tarnished or treated.
6. In a high polished condition copper gives off a bright but warm
feel and when tarnished can add to the more 'rustic appeal' of a setting.
7. Copper plating's role as an underlying coating in the decorative
finishing cycle is to 'seal' the substrate and provide for good 'adhesion' of
the plating to the substrate.
8. Copper can also be used to "rebuild" damaged or pitted surfaces
– providing a new working surface for the finisher.
9. Copper plating can deliver an alternative look for decorative
items and can be blackened, polished, or a combination of both for a
'bronzed' look.
10. Copper plating will be used in almost all decorative plating
processes involving the standard 'copper, nickel, chrome' (or copper, nickel,
gold) process.
13. Translate the following sentences into English.
1. Меднение, нанесение медных покрытий гальваническим
методом на обезжиренные и протравленные стальные или цинковые
готовые изделия, иногда на стальную проволоку.
2. Меднение часто применяется для защиты отдельных
участков стальных изделий от цементации (науглероживания).
3. Более распространённая область применения меди –
защитно-декоративное хромирование стальных или цинковых
изделий, при котором медь играет роль промежуточного слоя; поверх
меди наносится слой никеля, а на него – очень тонкий слой хрома
(0,25 мкм).
4. Различают два типа медных электролитов: кислые и
щелочные.
5. В кислых электролитах нельзя получить прочно сцепленные
медные покрытия на стальных и цинковых изделиях, так как в этом
случае железо и цинк в контакте с медью растворяются – нарушается
сцепление с покрытием.
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6. Цинковые изделия сложной формы подвергаются меднению
только в щелочных (цианистых) электролитах.
7. Процесс меднения распространен в промышленности и
используется не только как самостоятельный процесс, но и как
подготовительный процесс перед хромированием, никелированием и
серебрением.
8. Применение меднения как подготовительной операции
обусловлено тем, что медь очень прочно держится на стали,
выравнивает дефекты поверхности и другие металлы очень хорошо
осаждаются на медь, а на чистую сталь - плохо.
9. Поверхность изделий перед началом процедуры меднения
обязательно должна быть обезжирена и протравлена.
10. При нанесении медных покрытий из серно-кислого
электролита медные аноды растворяются в основном с образованием
двухвалентных ионов, которые, разряжаясь на катоде, осаждаются в
виде металлической меди.
13. Translate the following word combinations.
Двухвалентные ионы – discharge of copper – металлическая
медь – waste-treatment process – разряжаться на катоде – printed –
circuit board – серно-кислый электролит – high temperature lubricant –
подготовительный процесс – cyanide-based solution – медные аноды –
enhancing the brazing conductivity – контактное выделение меди –
buffed copper – защитно-декоративные покрытия – hydrogen bubbles.
14. Give the definitions of the words and word combinations.
1. Carbonisation is … .
2. Sonotrode is … .
3. Throwing power is … .
4. Diffusion is … .
5. Silvering is … .
15. Describe the process of thermal treatment.
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Unit 13.
16. Answer the following questions using texts from Unit 13.
1. Define copper plating.
2. What types of copper plating electrolytes do you know?
3. Where can people use copper plating?
17. Summarize the general ideas developed in all the texts of the
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Unit 14
А
В
CHROMIUM PLATING
1. Read the international words, guess their meanings and give
the Russian equivalents.
Perfect, chrome, vacuum, metallized, element, reflection,
motorcycle, hydrochloric, functional, Vicker, plastic, efficient, babbitt,
cylinder, substance, engineering.
2. Read and translate the following verbs.
To paint, to call, to reflect, to range, to rebuild, to distort, to resist,
to suffer from, to wear, to rig, to evaluate, to discolor, to bear, to except, to
put on, to harden, to cut.
3. Match the English phrases from column A with the Russian
phrases in column B.
1) chrome plating
2) muriatic acid
3) hydraulic cylinder
4) cylinder liner
5) working surface
6) casehardened steel
7) babbitt alloy
8) molding die
9) plating rate
10) lay person
11) anti-galling properties
12) cathode efficiency
a) гидравлический цилиндр
b) рабочая поверхность
c) пресс-форма
d) скорость образования
покрытия
e) баббитовый сплав
f) непрофессионал
g) хромирование
h) свойства противозадирной
смазки
i) выход по катодному току
j) закаленная сталь
k) хлористо-водородная кислота
l) вставная гильза цилиндра
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4. Read and translate the text. Summarize it in Russian.
Chrome is slang for Chromium, one of the 92 naturally occurring
chemical elements. Chrome is a metal, but it is not useful as a solid, pure
substance. Things are never made of solid chrome.
A cause of occasional confusion is the fact that people may tend to
describe any shiny finish as "chrome" even when it really has nothing to do
with chromium. For example, brightly polished aluminum motorcycle parts,
electropolished stainless steel boat rigging, vacuum metallized balloons and
helmets, shiny painted wheels, and nickel plated oven racks are sometimes
called 'chrome' by the lay person.
Chrome plating is more reflective (brighter), bluer (less pale,
grayish, or yellowish), and more specular (the reflection is deeper, less
distorted, more like a mirror) than other finishes. Put one end of a yardstick
against a bright finish, and see how many inches of numbers you can
clearly read in the reflection - you can clearly see the clouds in the sky
reflected in chrome plating. And there's a hard to define "glint" to top
quality chrome plating that nothing else has.
Chrome plating is generally used for one of two purposes: for
decorative uses or for engineering purposes. Chrome plating is used to
provide a very high degree of hardness on the surface of a metal to enhance
wear resistance, reduce friction, provide anti-galling properties, and, in
some cases, improve corrosion resistance. Chrome plating is an electrolytic
process that can be applied to regular steel, stainless steel, aluminum, and
other materials. (From www.finishing.com)
5. Read the text again. Decide whether the following statements
are true or false.
1. Chrome is the combination of chromium and sulphur acid.
2. Chrome plating is brighter, less pale and the reflection is deeper
than other coatings.
3. Chrome plating is mostly used for the following purposes: for
household activities, designing or for shipbuilding purposes.
4. Chrome plating is an electrochemical process that can be applied
to various materials.
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